The Holy Shroud (or Burial Cloth) of Turin

The Shroud of Turin is a linen burial cloth 4.42 metres long by 1.13 metres wide, woven in a four-thread herringbone pattern, a type of weave attested in Syria and Palestine in the 1st century. It bears the double imprint of a human body: a frontal image and a dorsal image, placed head to head, as if the cloth had been folded over and under the reclining body to wrap it as a shroud. The shroud has been kept since 1578 in the Cathedral of Saint John the Baptist in Turin in the Chapel of the Holy Shroud designed by Guarino Guarini (1668-1694).

The Shroud nevertheless had to leave Turin during the Second World War. From September 1939, for fear of bombing, it was taken to Rome, to the Quirinal Palace; then, to remove it from the covetousness of Hitler, who had had the Holy Lance transferred from Vienna to Nuremberg in 1938, the King of Italy asked the Holy See to ensure its safekeeping. Monte Cassino, first considered, was entirely destroyed in 1944; the territorial abbey of Montevergine, an isolated sanctuary at 1,200 metres altitude in the province of Avellino, in Campania, was preferred. On 7 September 1939, a telegram from the Substitute of the Secretariat of State, Msgr Giovanni Battista Montini, the future Paul VI, summoned the Benedictine abbot to the Vatican; the reliquary arrived at the abbey on the night of 25 September 1939 and was hidden under an altar of the convent church, with only the prior, the vicar general and two monks in the secret. Cardinal Maurilio Fossati, Archbishop of Turin, came to retrieve it on 28 October 1946^[2].

Before examining the scientific arguments in favour of its authenticity, which have nourished an abundant scientific literature for more than a century, its historical itinerary should be retraced. Jean-Christian Petitfils, in his reference work Le Saint Suaire de Turin (Tallandier, 2022), reconstructs fourteen centuries of translatio documented by Byzantine, Crusader and Western sources: from Jerusalem to Turin in six successive stages.

Before Edessa: two ancient patristic echoes

Even before the Edessan tradition becomes traceable in the sources, two ancient Christian witnesses preserve the memory of a shroud linked to the Resurrection. Saint Jerome, in his De viris illustribus (around 392), quotes a passage from the Gospel of the Hebrews, an apocryphal text dated to the 2nd century, according to which the risen Christ entrusted his sindon to the servant of the high priest before appearing to Saint James^[3]. A little later, in his youthful preaching in Jerusalem, Saint Cyril of Jerusalem evokes “the shroud, witness of the Resurrection”^[4], a sign that a precise burial cloth remained identified in the Christian memory of Jerusalem, well before the Edessan itinerary became documentable step by step.

Origin and Byzantine tradition

Byzantine tradition traces the Mandylion (or “Image of Edessa”) back to the apostolic age, a cloth on which the image of Christ is said to have been supernaturally imprinted. The Mandylion is attested at Edessa (present-day Şanlıurfa, Turkey) from the 6th century, then transferred to Constantinople in 944 AD. Several researchers (notably Ian Wilson, a British historian) have proposed that the Mandylion and the Shroud of Turin are one and the same object, simply folded so as to show only the face^[5].

The founding legend, transmitted by the Doctrine of Addai (an anonymous Syriac text dated between 390 and 430) and taken up by the Armenian historian Michael of Khoren in the 5th century, links the image to the conversion of King Abgar V of Edessa, healed by an envoy of the apostle Thaddeus bearing a cloth marked with the face of Christ^[6]. The oldest known literary witness to this devotion is Bishop James of Sarug (450-521), whose Homily on the Image of Edessa attests its veneration from the very beginning of the 6th century^[7]. A Syriac hymn of 569 celebrates the rebuilding of the cathedral of Edessa after the floods of 525: it was precisely on the occasion of these works that the image is said to have been rediscovered, according to Ian Wilson, in a niche in the rampart where it had been hidden^[8]. Finally, the Byzantine court physician Smira, known only through later manuscripts and given no precise century by Petitfils, is presented in this late tradition as describing an image representing “not only the features of the face, but the stature of the whole body”^[9]. A late legendary witness, this text does not by itself confirm that the cloth venerated at Edessa bore a complete bodily imprint.

Disappearance during the Fourth Crusade

In 1204, during the sack of Constantinople by the Crusaders, the Sydoine seen by Robert de Clari at Saint Mary of Blachernae disappears after the capture of the city. Robert de Clari, a knight taking part in the crusade, testifies: “There, there was the Sydoine in which Our Lord was wrapped… and no one, neither Greek nor French, ever knew what became of it after the capture of the city”^[10]. Petitfils nevertheless distinguishes this relic from the object kept at the Pharos, still attested after 1204: identifying the Sydoine of Blachernae with the Mandylion or the Shroud is therefore an author's thesis, not an established fact.

A document found later sheds light on this troubled period: a letter from the Byzantine nobleman Theodore Angelos Komnenos to Pope Innocent III, dated 1 August 1205, exhumed in 1981 in the Neapolitan archives of Santa Caterina a Formiello and palaeographically authenticated by the historian Barbara Frale, documents the fate of the relics of the Pharos in the months following the sack of the city^[11].

Appearance in France (1357)

The shroud officially reappears around 1357 at Lirey (Champagne), in the hands of the knight Geoffroy de Charny. It then passes through the House of Savoy, then is transferred to Turin in 1578 by Duke Emmanuel Philibert and kept ever since in the Chapel of the Holy Shroud by Guarino Guarini (completed in 1694) at the Cathedral of Saint John the Baptist, being publicly exposed only on rare occasions (expositions of 1978, 1998, 2000, 2010, 2015).

Summary chronology of the Shroud

On 28 May 1898, during an exposition in Turin, the photographer Secondo Pia is authorised to take the first official photograph of the shroud. Developing his plates in his darkroom, he discovers in astonishment that the photographic negative makes the image appear in positive, with a sharpness and realism never suspected^[22]:

“There is no doubt, this cloth bears the extremely realistic imprint of a man dead crucified in the manner of Roman antiquity. [...] To our knowledge, there is no other Roman condemned to crucifixion who at the same time underwent a scourging, a crowning with thorns and a lance thrust [all the elements found inscribed in the image of the Shroud].” Quoted from Yves Delage and Paul Vignon, conclusion of their study on the Shroud, presented to the Academy of Sciences of Paris in 1902^[23]

The communication caused a scandal; Delage explained himself publicly:

“If, instead of Christ, it had been a question of some Sargon, an Achilles or a Pharaoh, no one would have found anything to object to.” Quoted from Yves Delage, letter to Charles Richet, director of the Revue scientifique, published on 31 May 1902^[24]

The fact that the image of the Shroud is a perfect photographic negative is extraordinary for two reasons: (1) the concept of photography did not exist before the 19th century, so a medieval forger would have had no reason to produce a negative instead of a classical image; (2) this shows that the image is not a painting, because no pictorial process naturally produces a negative.

The first argument is medico-anatomical: the body imprinted on the Shroud is that of a genuine Roman crucified man, presenting all the wounds of the Gospel Passion, with an anatomical precision that medieval science totally ignored. This is the investigation conducted from the 1930s by the French surgeon Pierre Barbet (Saint Joseph Hospital, Paris), then continued by Sebastiano Rodante, Robert Bucklin (forensic physician of Los Angeles County) and more recently by F. Giraud, T. Castex and Y.-M. Giraud (2017).

The space of Destot, a nail impossible to invent

Surgeon Pierre Barbet demonstrates experimentally on fresh cadavers that the nail driven into the middle of the fold of flexion passes obliquely into the space of Destot of the carpus, without breaking a single bone, fulfilling Scripture (John 19:36 and Psalm 34):

“Each time, therefore, the nail had entered the passage known to anatomists under the name of the “space of Destot”, pushing aside, as Scripture had said in a premonitory way, “without breaking a single one” of the bones that enclose it. Pierre Barbet considered that the Roman executioners, trained in this mode of capital execution, knew this preformed anatomical passage perfectly.” Quoted from Jean-Christian Petitfils, Le Saint Suaire de Turin, Tallandier, 2022, p. 214^[25]

Medieval iconography systematically placed the nails in the palm, an anatomical impossibility: a body suspended by the palms would tear away. No medieval forger would have known to replace the nail at the wrist nor known the space of Destot.

The reflex retraction of the thumb (median nerve)

During his experiments on amputated arms, Barbet notes that penetration of the nail injures the median nerve, causing a reflex retraction of the thumb into the palm. This explains the troubling absence of visible thumbs on the image of the Shroud, a neurophysiological detail impossible to anticipate in the Middle Ages^[26].

The two directions of the blood flows

Barbet discovers that the crucified man had to alternate straightening up (to breathe) and sagging, which produces two blood flows in different directions on the arms, perfectly reproduced on the Shroud:

“To instinctively escape death and recover his breath, the condemned man was obliged to pull on his arms [...]. How could a forger of the Middle Ages have imagined such details when nothing was known at the time about the mechanisms of blood coagulation?” Quoted from Jean-Christian Petitfils, op. cit., p. 215^[27]

The lance thrust and the pericardial fluid (Jn 19:34)

Barbet verifies on autopsies that the lance driven obliquely into the fifth right intercostal space (Roman technique) perforates the right atrium and makes blood AND pericardial fluid (“water”) spurt out, exactly what Saint John reports (Jn 19:34). The hydropericardium is explained by a traumatic serous pericarditis due to the prior scourging^[28].

Blood at the heels (horizontal post-mortem transport)

Barbet notes that blood flowed abundantly towards the heels, a phenomenon that could only have occurred after the descent from the cross, during the horizontal transport of the body to the tomb. A post-mortem detail consistent with gravitational mechanics^[29].

The helmet of thorns (about 50 marks) and the scourging (about 120 marks)

Minute study reveals that it is not a simple crown but a genuine helmet of torture fitted with sharp spikes, held by a band of rush or hard straw:

“The Shroud speaks: some fifty wounds, including 13 perforations of the scalp clearly evident on the forehead and front of the head and 20 in the occipital region.” Quoted from Jean-Christian Petitfils, op. cit., p. 212^[30]

To this are added about 120 scourging marks over the whole body, precise signatures of the Roman flagrum taxillatum (a whip with thongs fitted with small lead balls). The clinical and colorimetric study of 2017 by F. Giraud, T. Castex and Y.-M. Giraud quantifies the damage suffered:

“His skin and muscles are lacerated over nearly 900 cm². His scalp is torn, he has bled, he has a thoracic contusion making breathing difficult and painful, effusions are forming in his pericardium and pleura, and his kidneys are virtually destroyed.” Quoted by Jean-Christian Petitfils, op. cit., p. 389-393^[31]

The cumulative energy released by the scourging corresponds to about 4,000 joules, that is, the power of some ten blows delivered by a heavyweight boxer.

The time window of 36-40 hours (Rodante)

The Italian physician Sebastiano Rodante (Syracuse) demonstrates clinically that the blood lesions of a cadaver can be transferred onto a burial cloth only if contact between body and cloth lasts between 36 and 40 hours, no less (the crusts remain intact), no more (fibrinolysis liquefies everything). That is precisely the duration of the Holy Sepulchre, from Friday evening to Sunday morning^[32].

Decisive detail: complete nudity

The man of the Shroud is represented entirely naked, implausible for a medieval artistic commission:

“The buttocks and perhaps the genital region, naked, which would have been considered another impropriety. The bishop or prior who had commissioned the shroud from the artist, monk or layman, would not have failed to require that the perisoma surrounding the pelvis be added. This is so true that, on certain copies, the perisoma was added.” Quoted from Yves Delage, 1902, quoted by Petitfils, op. cit., p. 206^[33]

→ Argument 1 summarised: the body imprinted on the Shroud is that of a real Roman crucified man, presenting all the wounds of the Passion (Jn 19), with anatomical precision (space of Destot, retraction of the thumb, hydropericardium, horizontal transport) inaccessible to medieval medical knowledge.

The second argument is physico-chemical: the image itself presents a bundle of properties that defy 21st-century science. No known technology, medieval or modern, can reproduce the image of the Shroud while simultaneously bringing together all the following characteristics.

The perfect photographic negative (1898)

As set out above, the image of the Shroud is a perfect photographic negative, a concept nonexistent before 1839. No pictorial process naturally produces a negative: light would be inverted there, which the eye cannot imagine without an apparatus. A medieval forger would have had no reason to produce a negative instead of a classical image, and no technical means to achieve it.

3D information encoded in the intensity (NASA VP-8, 1976)

In 1976, two US Air Force scientists, John Jackson and Eric Jumper, use a VP-8 image analyser (a device converting light densities into relief) developed by NASA to analyse the photograph of the Shroud^[34]. Major discovery: the image of the Shroud encodes three-dimensional information; the intensity of the browning varies according to the distance between the body and the cloth. No painting and no photograph naturally possesses this property.

According to Jackson and Jumper, the intensity of the image would vary with the distance between the body and the cloth, like relief information encoded in the image^[35].

A remarkable historiographical detail: well before Jackson, the French painter and engraver Gabriel Pascal Quidor (Grand Prix de Rome for engraving) had understood as early as 1913 that the image depended on the body-cloth distance. On 4 June 1913 he files a patent for a “photosculpture process making it possible to obtain without retouching the figure in relief”^[36], a French and earlier confirmation of the 3D character.

The isotropic image (Jet Propulsion Laboratory)

Donald J. Lynn and Jean J. Lorre, of the Jet Propulsion Laboratory in Pasadena (the American space laboratory of NASA), demonstrate by independent computer study that the image is isotropic, that is, without directional effect, without brushstrokes, without smearing. This definitively excludes any human intervention (painting, rubbing, application)^[37].

Superficial image (25-40 microns) without pigment

The STURP (Shroud of Turin Research Project) establishes in 1978 that the colouring of the Shroud is strictly superficial (25-40 microns thick, that is two to three fibrils), monochrome, without detectable pigment or dye, formed by dehydrating acid oxidation of the cellulose, a partial unexplained pyrolysis:

“The cellulose of the linen, under the probable effect of a sudden and mysterious rise in the temperature of the body, pyrolysed itself, without however entering into a complete process of carbonisation.” Quoted from Jean-Christian Petitfils, op. cit., p. 240-241^[38]

No image on the reverse of the cloth (Curto, 1974)

On 24 November 1974, Silvio Curto (professor of Egyptology) unstitches the Holland cloth that lined the Shroud. Despite the extreme fineness of the cloth, the image does NOT appear on the reverse, which excludes any through-impregnation typical of a painting, dye or chemical impregnation^[39].

Apparent weightlessness (equal intensity front and back)

The frontal and dorsal images present the same colour intensity, as if the body were floating, in weightlessness. A biochemical contact reaction should have accentuated the dorsal face crushed by the weight of the cadaver. A physically inexplicable detail^[40].

STURP (1978): 120 hours of analyses, an unresolved conclusion

In 1978, during the great Turin exposition, 40 scientists from NASA (the American space agency), the Los Alamos National Laboratory, the US Air Force Academy and the Jet Propulsion Laboratory of Caltech (the JPL, American space laboratory) carry out 120 hours of non-destructive examinations: X-ray fluorescence, infrared and Raman spectroscopy, optical and electronic microscopy, photography under ultraviolet rays (UV), under polarised light. This international study, known as the Shroud of Turin Research Project (STURP), publishes its final report in 1981^[41]. Central conclusion:

“The image is not the result of a painting, a dye, a chemical scorching, nor of any known technique. Its exact nature remains unexplained.”

The UV flash of Di Lazzaro (ENEA 2011), the only reproducible technology

The Italian expert Paolo Di Lazzaro (ENEA, Italian nuclear research agency) demonstrated in 2011 that the only technology capable of producing such an image in the superficial fibre of the linen is an ultra-short UV flash (about 10⁻⁸ second), a technology strictly inaccessible before the end of the 20th century^[42]. And even this technology reproduces only partially the properties of the Shroud, not the 3D information, not the complete isotropy.

→ Argument 2 summarised: the image of the Shroud brings together six physico-chemical characteristics (photographic negative, 3D, isotropic, superficial 25-40 μm, without pigment, without reverse, apparent weightlessness) of which no medieval technology could simultaneously dispose, and which even 21st-century science cannot reproduce in totality.

The third argument is biochemical: the brown stains of the Shroud are not paint, but indeed real human blood, presenting molecular signatures proper to a man dead under torture. Five scientific discoveries converge.

The Soret peak at 410 nm, porphyrin (Heller and Adler 1980)

By micro-spectrophotometry on the red fibrils, John Heller and Alan Adler detect at the Soret peak of 410 nanometres porphyrin (a component of haemoglobin), the unequivocal spectroscopic signature of human blood:

“All the red fibrils thus tested reached the “Soret peak” at 410 nanometres, a measurement used in spectroscopy for porphyrin molecules.” Quoted from Applied Optics, 15 August 1980, quoted by Petitfils, op. cit., p. 239^[43]

Blood group AB (Baima Bollone, 1982, a discussed result)

The biochemical analyses of Pierluigi Baima Bollone (professor of forensic medicine, 1982) attribute to the blood of the Shroud group AB, a rare group (a few percent of the world population). This old result, whose reliability as well as methodological independence remain debated, is compared by defenders of authenticity with those of the Sudarium of Oviedo and the Tunic of Argenteuil (see Argument 6) and with the Eucharistic miracles of Lanciano, Buenos Aires, Sokółka, Tixtla, Legnica (see article Eucharistic Real Presence, Objection 6)^[44].

Elevated bilirubin, haemorrhagic shock

Adler brings to light an exceptionally high level of bilirubin (bile pigment) in the blood of the Shroud, which explains on the one hand the atypical pink-carmine colouring of ancient blood (which should be black-brown), and on the other hand attests to violent ante-mortem traumas leading to haemorrhagic shock^[45].

The most striking testimony on this point is that of Barrie M. Schwortz, Jewish photographer and member of STURP, long sceptical about authenticity, precisely because of this abnormal red colouring. His intellectual conversion has remained famous in the sindonological milieu:

“The thing that prevented me from accepting that the Shroud is authentic during those years is that the blood on the Shroud was red in colour. Yet ancient blood must be brown or black. No one could explain to me how the blood on the Shroud could have remained red. And in 1995, in a telephone conversation with Dr Adler, a Jewish chemist, who proved that the blood on the Shroud was really blood, he told me something I had never heard of: when someone is tortured over a long period, the body enters a state of shock. Jesus received no water, he was scourged, he entered anaphylactic shock. After some time in this kind of shock, the walls of the blood cells begin to break down and the liver spreads into the blood an enzyme called bilirubin. And it happens that the blood remains red forever.” Quoted from Barrie M. Schwortz, testimony to the Marie de Nazareth association, reproduced in Matthieu Lavagna, Soyez rationnel, devenez catholique !, op. cit., p. 249^[46]

Serous halos and chronology: blood BEFORE the image

Ultraviolet examination reveals fluorescent serum halos around the clots and scourging marks (medico-legal signature of ante-mortem wounds). More crucially: under the dissolved blood stains, the linen is white, therefore the image formed AFTER the deposition of the blood, contradicting any pictorial fabrication in successive stages^[47].

Ferrihydrite nanoparticles (PLoS One, 2017, a contested study then retracted)

An atomic-resolution study published in PLoS One in 2017 by two institutes of the Italian Consiglio Nazionale delle Ricerche (Istituto Officina dei Materiali of Trieste + Institute of Crystallography of Bari), under the direction of Elvio Carlino and Giulio Fanti:

“It was established that the fibre was entirely covered with creatinine nanoparticles of 20 to 100 nanometres […] in which were included biological nanoparticles of 2 to 6 nm, composed of ferrihydrite. For these researchers, this would be proof that the man of the Shroud had been the victim of great suffering before being wrapped in the burial cloth.” Quoted from Jean-Christian Petitfils, op. cit., p. 325^[48]

Creatinine (a muscular waste that accumulates in the blood after violent effort or trauma) in abnormally high concentration, accompanied by ferrihydrite (an iron compound present in blood), serum biomarkers of a polytrauma, is interpreted by the authors as the mark of a man dead under the effect of a violent shock and massive haemorrhage, consistent with a crucifixion preceded by scourging. But this study, conducted on a single fibre, was contested then retracted by the journal a year later, the authors maintaining their viewpoint^[49]: it can therefore be invoked only as a debated hypothesis.

→ Argument 3 summarised: the blood of the Shroud is biochemically real human blood (porphyrin), attributed to group AB by Baima Bollone (discussed result), prior to the formation of the image, and bears, according to a since-retracted study, possible molecular biomarkers (creatinine, ferrihydrite) of a polytrauma with haemorrhagic shock. No medieval forger could simulate the molecular signatures detectable today.

The fourth argument concerns dating: the C14 dating published in 1988 (1260-1390), long presented as definitive proof of a medieval fake, is today seriously contested, and several alternative methods give results compatible with an ancient origin, with wide intervals and reservations.

The thunderclap of 1988 (1260-1390)

In 1988, three laboratories (Oxford, Tucson, Zurich) analyse a sample of the Shroud and conclude on a dating between 1260 and 1390. For decades, this result was presented as definitive proof of a medieval fake.

The statistical critique: heterogeneity (Casabianca et al., 2019)

The statistical archives of the three laboratories were obtained by judicial procedure in 2017 and analysed by statisticians Tristan Casabianca, Emanuela Marinelli, Giuseppe Pernagallo and Benedetto Torrisi in the journal Archaeometry (Oxford) in 2019^[50]. In substance, the authors conclude that the results of the three laboratories are statistically heterogeneous, to the point that one cannot ensure that they bear on a homogeneous sample, which weakens the dating published in 1988 and calls for a re-examination of the dossier, without however formally invalidating it.

Petitfils specifies the revealing discrepancies:

“The date ranges were not homogeneous: the figures of Oxford (1262-1312) did not overlap with the average of the two other laboratories (1353-1384). The measurement gap between Oxford and Arizona reached one hundred and four years, at which no one was surprised at the time.” Quoted from Jean-Christian Petitfils, op. cit., p. 280-281^[51]

More damning: “the raw results of the Tucson laboratory had provided dates later than 1355. The linen had not yet grown in the fields of the Near East when Geoffroy de Charny at Lirey was already showing the relic to the first crowds of pilgrims!”

As early as 1990, the Belgian chemist and statistician Remi Van Haelst had already quantified this heterogeneity: applying to the raw results of 1988 a χ² (chi-square) statistical test, he obtains a probability of coherence between the three laboratories below 1.3%, that is, the three measurements cannot statistically come from a genuinely homogeneous cloth^[52].

Contaminated sample: the zone rewoven in the Middle Ages (Rogers, 2005)

Microscopic analyses carried out by Raymond Rogers (Los Alamos National Laboratory), published in Thermochimica Acta in 2005^[53], demonstrate that the sample taken in 1988 came from a corner rewoven in the Middle Ages (presence of cotton not present in the rest of the shroud, traces of dye).

Rogers completes his analysis with vanillin: a decomposition product of the lignin of linen, which degrades over time at a known rate. The main cloth of the Shroud would contain, according to Rogers, NO detectable vanillin, which would suggest an age between 1,300 and 3,000 years, whereas the sample taken in 1988 would still contain some, an indication interpreted by Rogers as the mark of a more recent patching. This reading remains discussed: the Tucson laboratory for its part found no vanillin on its own threads^[54].

An indirect argument advanced by Rogers: the fire of Chambéry (1532). If the image came from an ancient organic painting, its components would have changed colour according to their proximity to the scorch marks. Yet, a fact noted by Rogers, no variation in the intensity of the image was observed anywhere on the cloth, an indication unfavourable to the hypothesis of an organic painting^[55].

3/1 herringbone weave (Raes, 1973)

Professor Gilbert Raes (University of Ghent) establishes in 1973 that the type of weave of the Shroud (“3 over 1 herringbone”), the Z twist of the threads (unusual but documented at Palmyra and in the Judean Desert) and the silky fineness characterise a very high-priced cloth prior to the 8th century. Presence in the loom of Gossypium herbaceum cotton from the Near East, a combination unknown to medieval Europe^[56].

WAXS 2022: a 1st-century dating still to be confirmed (non-destructive method)

On 11 April 2022, the international journal Heritage publishes the study by Liberato De Caro (Institute of Crystallography of the Consiglio Nazionale delle Ricerche of Bari) and Giulio Fanti (University of Padua), setting out the WAXS technique (Wide Angle X-Ray Scattering):

“There is set out a new dating technique called “Wide Angle X-Ray Scattering” (WAXS) consisting in measuring the ageing of the cellulose of the linen by means of X-rays and converting it into elapsed time, thanks to other samples of linen cloths dated between 3000 BC and AD 2000. At the end of their experiments, the authors arrived at the conclusion that the Shroud indeed went back to the 1st century of our era, being very close in its structure to a linen sample found in the ruins of Masada, the Jewish citadel fallen in AD 73.” Quoted from Jean-Christian Petitfils, op. cit., p. 325^[57]

To this are added the works of Giulio Fanti in 2013: three non-destructive methods (infrared spectroscopy, Raman, mechanical measurements) give, according to the method, wide intervals (about 300 BC to 400, 700 BC to 300 and 1 to 800), with possible perturbations and a contested provenance of the fibres. These results are compatible with an ancient origin, without dating the cloth to the 1st century^[58].

Assessment of the five dating methods

The table below compares the C14 dating of 1988 with the alternative methods. The latter give results compatible with an ancient origin, with wide intervals and reservations proper to each. The C14 dating remains isolated and statistically contested (heterogeneity, representativeness of the sample discussed, re-examination requested).

The Pray Codex (1192-1195): 68 years before the lower bound of the C14

The most decisive historical argument against the medieval dating is quite simply earlier by at least 68 years than the lower bound of the C14 (1260). It is the Pray Codex or Pray manuscript, a Hungarian liturgical collection kept at the Széchényi National Library of Budapest (shelfmark MNY 1), dated at the latest to 1192-1195^[59]. It contains the oldest text written in Hungarian and several pen miniatures heightened with blue and red, including two drawings (folios 27 verso and 28 recto) reproducing point by point the unique characteristics of the Shroud of Turin.

Petitfils lists the details reproduced from the 12th century:

“On the scene of the entombment, one sees the naked body of Christ, a unique case in iconography, with his characteristic beard, his long hair, his pectorals and his linear traces, the exact placement of the nail at the right wrist, the hands crossed, the right over the left, the long index finger, the absence of the thumb (folded inside the palm because of the lesion of the median nerve), the hands covering the lower abdomen and the thighs, so many details that are read on the Shroud and nowhere else.” Quoted from Jean-Christian Petitfils, op. cit., p. 83-84^[60]

In 2009, three French researchers, Thierry Castex, Éric de Bazelaire and Marcel Alonso, discover an additional detail that only direct observation of the Shroud could provide: on the lower miniature of folio 28 are reproduced the four small burn points in a square pattern (called “L holes” or “poker holes”) characteristic of the Shroud, prior to the Chambéry fire of 1532, as well as the specific herringbone weave^[61]. No 12th-century copyist could have invented these precise arrangements without having seen them.

Conclusion advanced by Petitfils and the defenders of authenticity: the Shroud already existed before 1192. This judgment rests on their iconographic identification of the details of the Pray Codex with those of the Shroud. No probability calculation is produced in support: it cannot be presented as an established impossibility.

→ Argument 4 summarised: the 1988 C14 is weakened by (a) the statistical heterogeneity of the results, to be re-examined, (b) the contested representativeness of the sample (discussed zone), (c) the divergence of analysis on vanillin between the sample and the rest of the cloth. Raes 1973 (compatibility of ancient weave, not a dating), Rogers 2005 (vanillin, discussed reading) and Fanti 2013 (wide intervals, provenance of fibres contested) give results compatible with an ancient origin, and the WAXS study of De Caro and Fanti 2022 proposes a compatibility with the 1st century under hypotheses, to be confirmed. Finally, the Pray Codex (1192-1195) documentarily attests the existence of the Shroud 68 years before the 1988 C14 lower bound.

The fifth argument is palynological and mineralogical: particles present on the Shroud betray a direct stay in the Near East, notably in Palestine, at Constantinople and in Anatolia, precisely the presumed route of the shroud.

Pollens from the Near East (Frei-Sulzer 1973, Lucotte 2007)

The analysis of pollens present on the Shroud, carried out by the Swiss criminologist Max Frei-Sulzer (founder of the scientific criminology laboratory of the Zurich cantonal police) in the 1970s, on adhesive tapes taken in 1973 and 1978, led to the claimed identification of 58 species of pollen, several of which were linked by Frei to plants of the Near East (Palestine, Anatolia, Constantinople). These identifications have been discussed and partially re-examined since: they cannot be presented as species proper to Palestine alone^[62].

More than thirty years later, geneticist Gérard Lucotte resumed the examination under a scanning electron microscope, on a limited sample, and Petitfils reports that he identified five additional pollens beyond Frei's list (publication reported in 2007):

“Three belonged to the species Ceratonia Siliqua (carob tree), one to the species Balanites aegyptiaca (desert date palm) and one to the species Cercis siliquastrum (Judas tree). [...] This discovery was all the more interesting because this type of pollen is never transported by the wind, but by insects, which considerably reinforces the probability of a stay of the Shroud in Palestine.” Quoted from Jean-Christian Petitfils, op. cit., p. 320^[63]

Petitfils links the Judas tree and the carob tree to Galilee, Samaria and Judea. This linking rests on the sample examined by Lucotte and on Frei's identifications: it remains discussed and does not suffice, by itself, to establish a stay of the Shroud in Palestine.

Jerusalem limestone aragonite (Kohlbeck-Nitowski, 1986)

The X-ray analysis by Joseph Kohlbeck and Eugenia L. Nitowski published in Biblical Archaeology Review in 1986 revealed the presence of microscopic grains of limestone aragonite near the feet of the Shroud, whose chemical signature is identical to that of the tombs of the Jerusalem region (and different from European aragonites)^[64].

Early Christian inscriptions (Barbara Frale, 2009, a much-discussed hypothesis)

Historian Barbara Frale, archaeologist at the Vatican Apostolic Archives and specialist in Jewish funerary rites of the 1st century, publishes in 2009 a palaeographical reading of the “ghosts of writing” present around the face of the Shroud, in consultation with Simone Venturini (biblical Hebrew), Marco Buonocore (Greek epigraphy) and Father Émile Puech (École biblique et archéologique de Jérusalem). This is a much-discussed hypothesis, not an established finding:

“The palaeographers consulted by the Italian historian considered that this archaic mode of writing belonged to the early Christian world (1st-4th century). According to Mario Capasso, palaeographer and papyrologist, the angular sigma Σ was used in the 1st century of our era, before disappearing in the 2nd. The writings on the Shroud would therefore go back to the death of Christ.” Quoted from Jean-Christian Petitfils, op. cit., p. 312^[65]

Frale proposes reading there notably the groups HΣOY (centre of Iēsou, “Jesus”), NNAZARENNOΣ (“Nazarene”), INNΣ (formula of condemnation) and PEZω (pronounced “Rezô”, a signature in clear attributed to the Roman official). But the complete reconstruction she draws from it, a supposed burial permit dated 7 April 30, is judged by Petitfils himself “clearly an overinterpretation”, and critics (Di Lazzaro, Murra and Schwortz in 2013, Jordan et al. in 2015) see in it only an effect of pareidolia: the reading of letters in the simple interlacing of fibres^[66]. Only the presence of several of these letter groups, recorded independently by several researchers with different methods, remains attested.

The Jewish shroud of Akeldama (Shimon Gibson, 2010)

A major archaeological discovery of January 2010 by the British archaeologist Shimon Gibson: in the Jewish cemetery of Akeldama, near Jerusalem, a shroud dated to the 1st century AD is unearthed, which covered the whole body and passed over the head (remains of hair were found there)^[67].

This discovery refutes the exegetical thesis according to which Jesus would have been wrapped “like a mummy” in bands, and not in an integral cloth, confirming that the form of the Shroud of Turin conforms to Jewish funerary practices of the 1st century in Palestine.

→ Argument 5 summarised: four distinct material traces (pollens linked by Frei, then by Lucotte on a limited sample, to plants of the Near East, identifications discussed and partially re-examined; aragonite compared to that of Jerusalem; traces of writing whose reading remains debated; conformity to the Akeldama model) are presented by defenders of authenticity as suggesting a stay of the Shroud in Palestine in the 1st century.

The sixth argument is comparative: the Shroud of Turin is not isolated; it belongs to a trio of relics of the Passion (Shroud, Sudarium of Oviedo, Tunic of Argenteuil) whose independent scientific analyses converge.

The Sudarium of Oviedo (Goldoni 1993)

The Sudarium of Oviedo (Spain) is a bloodied cloth that is said to have covered the face of Jesus according to John 20:7. According to the tradition reported by late sources, notably Bishop Pelayo of Oviedo in the 12th century, it is said to have been kept in Spain since the 7th century. Petitfils (p. 322) makes this ancient history rest on late witnesses, whose reliability is imperfect: neither this antiquity, nor the absence of direct contact with the Shroud, is established by contemporary sources. Only the material analyses reported below are retained here as data:

“In June 1993, Dr Carlo Goldoni identified the blood present on the sudarium of Oviedo as group AB, the same as on the Shroud. The stains were composed for one part of blood and for six others of pulmonary fluid. It was possible to establish that the nose measured 8 cm long, that it was swollen in the middle of the right side, doubtless broken by a fall, that the victim bore a short beard and moustaches stained with blood, that his mouth was half-open and that part of his hair was tied in a braid, as the Holy Shroud revealed. The similarity between certain stains of the two cloths was perfect.” Quoted from Jean-Christian Petitfils, op. cit., p. 334^[68]

The tradition of a separate stay of the Sudarium from the 1st century, reported by these same late sources, is not established by contemporary sources. According to the reported analyses, the two cloths would bear the same precise anatomical traces: broken nose, blood attributed to group AB, concordant wounds. Defenders of authenticity see in this an argument against the hypothesis of a coordinated medieval fraud, if these typings are reliable and independent, a debated condition (see below).

A piece of linen 84 cm by 53, kept today in the Cathedral of Oviedo and covered with blood and serum stains, this sudarium was analysed by a Spanish and American multidisciplinary team, which showed, writes Petitfils, the “perfect correspondence of the blood flows of the face with those of the Shroud”^[69].

The Tunic of Argenteuil, 9 superpositions out of 10 (Marion, 1997)

The Holy Tunic of Argenteuil (France, kept since the 9th century) is according to tradition the under-tunic worn by Jesus during the Passion (Jn 19:23). André Marion, an engineer (who had previously detected the “ghosts of writing” on the Shroud), reports in 1997, by improved instruments, that nine blood stains out of ten of the Tunic of Argenteuil would geometrically superpose onto those of the Shroud^[70].

DNA on the Tunic (Gérard Lucotte)

Geneticist Gérard Lucotte detects that the Tunic of Argenteuil is “soaked in blood” and extracts a DNA sequence with fifteen genetic markers of the person who stained it, demonstrating authentic human blood^[71].

Joint AB probability on three relics (1 in 8,000, conditional calculation)

Blood group AB is announced independently on the Shroud (Baima Bollone 1982), the Sudarium of Oviedo (Villalain Blanco and Goldoni 1993) and the Tunic of Argenteuil (Saint-Prix and Lucotte 1986-2005). If one holds these three analyses to be reliable and independent, the joint probability that three samples taken at random are all AB would be 0.00125, that is 1 chance in 8,000^[72]. But this double condition, reliability of each old analysis, real independence of the three measurements, is itself debated: the figure has meaning only inside this hypothesis.

→ Argument 6 summarised: the Shroud is not isolated. Three relics of the Passion (Turin, Oviedo, Argenteuil), which tradition has kept in three distinct places since the 7th-9th century, without their ancient separation nor the absence of contact being established by contemporary sources, bear, according to these analyses, human blood of the rare group AB, with geometric superpositions of the wounds reported by Marion. If these AB typings are reliable and independent, a debated condition, defenders of authenticity see in this an argument against a coordinated medieval fraud.

The seventh argument is iconographic: the face of the Shroud is massively reproduced in Byzantine and medieval Christian art, even though this art is supposed to be earlier by several centuries than the Western appearance of the Shroud at Lirey in 1357. Christian iconography presupposes the Shroud as a model, a thousand years before its discovery by the modern West.

The 15 signs of Vignon

Paul Vignon identifies fifteen characteristic traits of the face of the Shroud (frontal transverse line, V on the nose, right eyebrow higher, forked beard, asymmetrical locks, line under the chin due to a false fold, etc.) which appear simultaneously in Christic iconography from the end of the 4th century, precisely at the moment of the arrival of the Shroud at Edessa (387-388).

Percentage of Vignon signs present in the major icons:

• Christ Pantocrator of Daphni (11th century): 11 signs out of 15
• Sant'Angelo in Formis (10th century): 13 signs out of 15
• Cathedral of Cefalù (12th century): 14 signs out of 15

Christ Pantocrator of Sinai: 250 superposition points (Whanger)

Dr Alan D. Whanger (physician, former missionary of the Methodist Church) records, according to his polarised image superposition method, 250 points of convergence between the face of the man of the Shroud and the Christ Pantocrator of the Monastery of Saint Catherine of Sinai (encaustic icon, 6th century), which he compares to the 60 points he presents as the American judicial identification threshold^[73].

Sinai is a Byzantine icon 750 years earlier than the Western appearance of the Shroud at Lirey. For Whanger, this convergence would plead for a painting after the Shroud, therefore for its existence in the 6th century; this reasoning depends on the reliability of his superposition method.

Byzantine numismatics

From the Council in Trullo (691), Emperor Justinian II has gold solidi struck presenting Christ Pantocrator with a frontal blood flow identical to the Shroud. Whanger finds 145 superposition points with this solidus. Of the 187 Byzantine coins referenced between 944 and 1204, 172 bear the face conforming to the standard model^[74].

→ Argument 7 summarised: since the 4th century, Byzantine and medieval Christian iconography presents the face of Christ with 15 characteristic signs compared to the Shroud. The Pantocrator of Sinai (6th century) presents 250 superposition points with the Shroud according to Whanger's method, compared by him to the 60 points of the threshold he cites. Byzantine numismatics (691-1204) reproduces the same model. For Whanger, the Shroud existed from the 4th century and inspired this iconography; this conclusion depends on the reliability of his method.

The eighth argument is resurrectional: the formation of the image itself remains scientifically unexplained after 124 years of research since Secondo Pia (1898). The mode of separation of the body and the cloth, without the slightest trace of tearing on the blood clots, suggests a physically extraordinary event, which Christian tradition identifies with the Resurrection.

The image formed without contact tearing

Petitfils summarises the enigma in his chapter XVII:

“No one can scientifically explain how the dead man could have come out of it without leaving the slightest trace of tearing on the blood clots or the linen fibrils. [...] In the case of the Shroud which plays the role of a dressing, the blood stains are visible on the front and back of the cloth; the blood therefore passed through it and, in thirty-six hours, had all the time to dry and stick the Shroud to the innumerable wounds. On examination of the Shroud, none of the hundreds of stains has an irregular or torn outline. One must face the evidence: the body disengaged itself from the Shroud without leaving the slightest trace of separation.” Quoted from Jean-Christian Petitfils, op. cit., p. 412^[75]

This is a phenomenon medico-legally impossible on a normal cadaver: any normal transport or removal of a cadaver whose wounds are stuck to a burial cloth tears the clots and leaves tears on the fibrils. None of the hundreds of stains of the Shroud presents tearing.

Mysterious pyrolysis of the cellulose

The image is not a painting: it is a dehydrating acid oxidation of the cellulose penetrating only 25-40 microns (two to three fibrils). This partial pyrolysis is physically inexplicable from a dead body; a cadaver releases no thermal energy capable of producing such a reaction.

The UV flash: the only reproducible technology, inaccessible

Paolo Di Lazzaro (ENEA 2011) demonstrated that the only technology capable of reproducing, partially, the image of the Shroud is a UV flash of very short duration (about 10⁻⁸ second) and very strong intensity. This suggests that the image formed by an intense and brief radiation emanating from the body itself, a phenomenon physically compatible with the Resurrection of Christ understood as the instantaneous passage of the dead body to the glorified body.

Paul Claudel: “presence”

The poet Paul Claudel contemplates in 1935 the photographs of the knight Pia and writes:

“An importance so great that I can compare it only to a second resurrection. [...] The interval of nineteen centuries is annihilated at a single stroke, the past is transferred into the immediate. [...] It is not simply an official piece, as would be for example a report, a duly signed and initialled judgment: it is a decal, it is an image bearing with it its own guarantee. More than an image, it is a presence.” Quoted from Paul Claudel (1935), quoted by Petitfils, op. cit., p. 413^[76]

→ Argument 8 summarised: the formation of the image and the detachment of the body without tearing of the clots constitute a phenomenon medico-legally and physically inexplicable by known natural means. The only technology partially reproducing the image is a modern UV flash, suggesting a brief and intense radiation emitted by the body itself at the moment of separation. Christian tradition identifies this phenomenon with the Resurrection of Christ.

No serious dossier of authenticity is complete without confrontation with the best adverse objections. Five great sceptical theses have been defended since the end of the 19th century. None survives the test of current scientific data, but it is important to set them out in their strongest form before answering. This is the only way to show that the conclusion of authenticity does not rest on a Catholic parti pris, but on a convergence of university analyses arriving independently at the same result.

Objection 1: The letter of Pierre d'Arcis (1389), “cunningly painted”

Adverse thesis. In 1389, the Bishop of Troyes Pierre d'Arcis addresses to the Avignon antipope Clement VII a memorandum denouncing the exposition of the Shroud at Lirey. According to this document, the shroud had been “cunningly painted, the truth having been attested by the artist who had painted it”. This is the classical historical argument of the sceptics.

Answer. The historian and archivist Emmanuel Poulle (1928-2011), member of the Institute and former director of the École nationale des chartes, published in 2006 a masterly rehabilitation of the Lirey dossier. He demonstrates that the letter of Pierre d'Arcis is an undated, unsigned, unsent draft, found in the diocesan archives of Troyes; its content rests entirely on rumours (“it is said”, “I was told”) without naming the supposed artist; and more seriously still, Pope Clement VII contradicts the memorandum by authorising the exposition by his bull of 6 January 1390^[77]. Conclusion:

“The Lirey dossier, long presented as the historical proof of fraud, is in reality the expression of a jurisdictional conflict between Pierre d'Arcis and the chapter of Lirey over exposition rights, not a testimony on the authenticity of the relic. No “confessed artist” is ever named.” Quoted from Emmanuel Poulle, Revue d'histoire de l'Église de France, vol. 92, 2006^[78]

To this is added the iconographic argument of the Pray Codex (1192-1195), earlier by 165 years than the exposition of Lirey: the Shroud is documented in Hungary two centuries before the supposed “fabrication” denounced by Pierre d'Arcis.

Objection 2: Walter McCrone (1980), “iron oxide painting”

Adverse thesis. The American micro-chemist Walter McCrone (1916-2002), a former member of STURP, declares on 19 September 1980 in the Times that he had found on the fibrils of the Shroud particles of iron oxide (Fe₂O₃) and vermilion characteristic of a medieval painting of the “Venetian red” type. For McCrone, the whole image would have been made “with wet fingers” with a gelatin-based tempera.

Answer. Three converging refutations have scientifically disqualified McCrone:

1. Optical spectra of STURP. Samuel Pellicori (Santa Barbara Research Center) measures the spectrum of the iron oxide present and demonstrates that it in no way enters into the composition of the image: the coloured fibrils of the image do not contain the spectral signature of Fe₂O₃^[79].
2. No medieval contaminants. Roger Morris and Larry Schwalbe (Los Alamos), under the X-ray fluorescence microscope, show that the very rare iron particles are uniformly distributed over the whole cloth in grains smaller than a micron, without manganese, nickel or cobalt (obligatory companions of medieval ochres). This is the natural residue of the retting of linen, not of painting^[80].
3. No peer-reviewed journal. McCrone never published his analyses in a peer review journal. His articles appeared in The Microscope, the journal published by his own laboratory, Walter McCrone Associates Inc., without an independent external reading committee^[81].

Petitfils considers McCrone's theses “scientifically disqualified”, while noting that several critical authors continue to refer to them^[82].

Objection 3: Luigi Garlaschelli (2009), “reproduction by bas-relief”

Adverse thesis. The Italian chemist Luigi Garlaschelli (University of Pavia) claims in 2009 to have reproduced the image of the Shroud. His method: coat a bas-relief of a human body with red ochre, apply a linen cloth, then age the cloth three hours at 215°C, treat with dilute sulphuric acid and cobalt blue, and wash.

Answer. Petitfils summarises the failure:

“If the effect obtained was better, Garlaschelli was incapable of reproducing the set of properties of the original, in particular the half-tone gradation between the protruding contact zones and those of non-contact. His image was composed of coloured points of varied dimensions, and the blood stains of this pseudo-shroud did not present the fluorescent serum halo observed under the electronic microscope on the authentic one.” Quoted from Jean-Christian Petitfils, op. cit., p. 274^[83]

Seven distinct characteristics of the Shroud are missing from the Garlaschelli copy: (1) perfect photographic negative image; (2) 3D information encoded in the intensity; (3) isotropy of the image (without brushstrokes); (4) depth of 25-40 microns without penetration; (5) fluorescent halos of ante-mortem serum; (6) absence of image on the reverse; (7) bilirubin and porphyrin in the blood. No medieval method could simultaneously bring together these seven properties.

Objection 4: Nicholas Allen, Picknett and Prince, “proto-photography by Leonardo da Vinci”

Adverse thesis. The South African professor Nicholas Allen (1995) and the paranormal lecturers Lynn Picknett and Clive Prince (1994) propose that the Shroud is a proto-photograph made by Leonardo da Vinci: a cadaver suspended before a quartz lens in a camera obscura, printing the image on a cloth soaked in silver nitrate and ammonia. According to Picknett-Prince, the face of the Shroud would be that of Leonardo himself.

Answer. Besides the chronological absurdity (Leonardo was born on 15 April 1452, whereas the Shroud is documented at Lirey around 1357, nearly a century before), Petitfils notes three decisive objections:

“Large-diameter biconvex lenses did not exist at that time, and such a discovery would have spread like wildfire, inevitably triggering the serial production of false shrouds. The brown-purple proto-photograph made with this system presented relatively sharp contours, contrary to the image of the Shroud, and above all did not offer the characteristic of three-dimensionality.” Quoted from Jean-Christian Petitfils, op. cit., p. 274-275^[84]

The practical test was redone in 2005 for a History Channel documentary (Unraveling the Shroud of Turin) by producer Sean Heckman: the image obtained, blurred and without 3D relief, in no way resembles the Shroud.

Objection 5: Joe Nickell, “rubbing of a powdered bas-relief”

Adverse thesis. The American sceptic Joe Nickell (Skeptical Inquirer) proposes from 1983 that the image of the Shroud was made by rubbing: a wet cloth applied to a bas-relief, brown powder applied over it.

Answer. This hypothesis fails on the same points as Garlaschelli, but also on three specific data:

1. Complete isotropy verified by Donald J. Lynn and Jean J. Lorre at the Jet Propulsion Laboratory: the image has no directional trace (rubbings, strokes, blows). Yet any manual rubbing leaves trajectories detectable under the microscope^[85].
2. No 3D relief image in the Nickell method: his test cloth never produced the distance information encoded in the browning of the Shroud.
3. Blood BEFORE the image: the fluorescent serous halos and the white linen under the blood stains prove that the blood marks preceded the image, incompatible with any painting in superposed layers.

Synthesis: why the five objections fail together

Each objection, taken in isolation, is defensible by a stubborn sceptic. But none accounts for the cumulative bundle of the data of the Shroud. The table below shows it:

In the reading of Petitfils and the defenders of authenticity, no adverse hypothesis passes more than 2 boxes out of 11. This table, built by the defenders, illustrates their argument of explanatory asymmetry: it does not by itself constitute a demonstration, and no probability is calculated there.

The French historian Jean-Christian Petitfils, biographer of Louis XIV, eminent member of the academic community, laureate of several prizes of the Académie française and the Académie des sciences morales et politiques, published in 2022 Le Saint Suaire de Turin: Témoin de la Passion de Jésus-Christ (Tallandier, Paris, 480 p.). This work remains the French-language reference synthesis on the Shroud. It brings together the totality of scientific research published between 1898 and 2022, with more than sixty converging arguments, historical, archaeological, medico-legal, biochemical, iconographic and numismatic.

The eight thematic arguments presented above are the synthesis of the main arguments documented by Petitfils. For the exhaustive detail (notably on the critique of the C14 dating, the Byzantine history of the Shroud, the Hungarian Pray Codex of 1192-1195 which faithfully reproduces the unique characteristics of the Shroud sixty years before the C14 dating, the rehabilitation of the Lirey dossier by Emmanuel Poulle 2006, the patent of Quidor 1913 on 3D photosculpture, etc.), the reader is referred to the complete work.

The probabilistic calculation of Yves Delage (1902): 1 in 10 billion

From 1902, the Sorbonne zoologist Yves Delage, a notorious agnostic and materialist, applies rigorous Bayesian reasoning to the Shroud. The conjunction of five exceptional circumstances (Orient outside Egypt, wound in the right side, crown of thorns, duration of burial 24-72 h, nobility of the face) in another victim gives:

“There is a concourse of five circumstances [...]. Suppose that for each there is a one-in-a-hundred chance that they met in another person, there is therefore only a one-in-100-to-the-power-of-5 chance, that is in ten billion, that they met together. I do not give this, of course, as numbers having any claim to precision [...].” Quoted from Yves Delage, Revue scientifique, May 1902, quoted by Petitfils, op. cit., p. 209^[86]

This calculation was made on five traits only. Petitfils and the defenders of authenticity extend this reasoning to the eight contemporary arguments set out above and judge a fortuitous coincidence very improbable. No new calculation, with protocol and frequencies, is produced for the set of these eight arguments: this judgment remains that of the defenders, not an established probability.

When Yves Delage presented his communication to the Academy of Sciences of Paris on 21 April 1902, his text was not published in the Comptes rendus: the perpetual secretary Marcellin Berthelot refused to insert it there^[87].

Summary table of the eight arguments

The table below synthesises the eight arguments in a consultable format: each taken in isolation would perhaps resist an ad hoc critique; taken together, they saturate by convergence all degrees of reality, historical, anatomical, physico-chemical, archaeological, iconographic and theological.

Convergence as proof

Taken in isolation, each of the eight arguments would be debatable: this is the usual sceptical objection (“this particular argument can be contested”). Petitfils and the defenders of authenticity answer by their systemic convergence (historical, archaeological, medico-legal, biochemical, iconographic, numismatic, genetic) and judge very improbable an appearance by chance or by medieval fabrication. No protocol or global calculation is given for the whole bundle: this improbability is their judgment, not an established probability.

As Petitfils writes in closing his work:

“Who among believers or even unbelievers has not been fascinated by the contemplation of this face from beyond the tomb that has crossed the ages? Freed from suffering, noble and serene, of a grave and sublime majesty, it seems to pose to us the same question that Jesus the Nazarene already posed to his disciples on the roads of Galilee and Judea: “And you, who do you say that I am?”” Quoted from Jean-Christian Petitfils, op. cit., p. 413, conclusion^[88]

The Church does not dogmatically define the authenticity of the Shroud, out of pastoral prudence, in order not to condition faith on any material object whatsoever. But it honours it as a relic worthy of veneration (Reliquia), and the contemporary magisterium has spoken of it on numerous occasions with a tone of growing respect. A fundamental theological distinction is required: the authenticity of the Shroud is not a dogma, and is not destined to become one; but public devotion and private cult have been encouraged for more than a century.

Saint Pius X and Pius XI, magisterial evolution

Saint Pius X (1903-1914) publicly venerates the first photographs of Secondo Pia. Pius XI (1922-1939), previously Msgr Achille Ratti, former prefect of the Ambrosian Library of Milan, is at first rather sceptical. But examination of the photographs of Giuseppe Enrie (1931), reading of scientific studies and interviews with several scholars, including Pierre Barbet, convince him. On 23 March 1934, he grants a plenary indulgence to the faithful who venerate the Holy Shroud. Petitfils further reports that in 1936 Pius XI is said to have again expressed in very strong terms his veneration for the relic of Turin, without the exact formula having been found in a primary pontifical source^[89].

Saint John Paul II (1980, 1998), “a provocation to intelligence”

Saint John Paul II venerates the Shroud twice (April 1980 and May 1998). On the occasion of the exposition of 1998, he pronounces the most precise pontifical discourse ever devoted to the Shroud:

“The Holy Shroud is a provocation to intelligence. It requires above all the commitment of each man, in particular of the researcher, to grasp with humility the profound message addressed to his reason and to his life. The mysterious fascination exercised by the Holy Shroud pushes one to formulate questions on the relationship existing between the sacred Linen and the historical life of Jesus. Since this is not a theme of faith, the Church does not have the specific competence to pronounce on these questions. It entrusts to scientists the duty to continue research in order to succeed in finding adequate answers to the questions linked to this Shroud which, according to tradition, would have wrapped the body of our Redeemer when he was taken down from the cross.” Quoted from Saint John Paul II, discourse during the visit to Turin, 24 May 1998^[90]

Benedict XVI (2010), “an extraordinary icon”

Benedict XVI goes to Turin on 2 May 2010 for the exposition. His meditation, pronounced in the Cathedral of Saint John the Baptist before the exposed Shroud, sheds light on its theological meaning:

“One can say that the Holy Shroud is the Icon of this mystery, the Icon of Holy Saturday. [...] The Holy Shroud is an Icon written with blood; the blood of a man scourged, crowned with thorns, crucified and pierced in the right side.” Quoted from Benedict XVI, meditation before the Holy Shroud, Turin, 2 May 2010^[91]

More than 2.5 million pilgrims go to Turin for this exposition. Benedict XVI insists on the Christological dimension: the Shroud is not a magical object, but a sign calling for contemplation of the dead and risen Christ.

Pope Francis (2013, 2015, 2020), “icon of this love”

Pope Francis, who had had the AB blood of the Argentine Eucharistic miracles analysed when he was Archbishop of Buenos Aires^[92], joins by radio message the televised exposition of 30 March 2013 (Holy Saturday). On 21-22 June 2015, he goes in person to Turin for the bicentenary of the birth of Saint John Bosco and celebrates Mass on Piazza Vittorio. At the Angelus that follows, he declares:

“At the end of this celebration, our thoughts go to the Virgin Mary, loving and caring mother towards all her children, whom Jesus entrusted to her from the cross, while he offered himself in the greatest gesture of love. The Holy Shroud is an icon of this love, which once again has attracted so many people here, to Turin.” Quoted from Pope Francis, Angelus on Piazza Vittorio, Turin, 21 June 2015^[93]

During the Covid-19 pandemic, the Archbishop of Turin Msgr Cesare Nosiglia organises exceptional televised expositions on the Holy Saturdays of 11 April 2020 and 3 April 2021, broadcast worldwide on social networks. The pandemic will paradoxically have multiplied the worldwide diffusion of the Shroud.

Magisterial synthesis

Five popes, Saint Pius X, Pius XI, Saint John Paul II, Benedict XVI and Francis, have publicly manifested their veneration for the Shroud: Pius XI grants it a plenary indulgence in 1934; Saint John Paul II sees in it “a provocation to intelligence” (1998); Benedict XVI calls it the “extraordinary Icon” of Holy Saturday (2010); Francis contemplates in it “an icon of this love” (Angelus, 2015). None has pronounced on strict historical authenticity, because that belongs to science and not to dogma. But the unanimity of the magisterial tone, respectful, contemplative, never distanced, is in itself a sign: the Church does not treat the Shroud as a doubtful relic, but as a “sign” leading to the paschal mystery.

Related Ignispedia articles

• Did Jesus really exist?, a historical prerequisite
• The Resurrection of Jesus, the central event
• The divinity of Jesus, the theological stake of the shroud
• The blood improbability of the relics of the Passion, AB convergence Shroud + Oviedo + Argenteuil
• The nails: palms or wrists?, anatomical and iconographic debate
• The Shroud according to Maria Valtorta, complementary mystical corpus
• The limits of radiocarbon dating: to go further on the contestation of the 1988 C14 (statistical heterogeneity and representativeness of the sample discussed, re-examination requested)
• Eucharistic miracles, convergence with blood group AB
• Our Lady of Guadalupe, another comparable acheiropoietic image
• Cosmological fine-tuning, another scientific argument of Catholic apologetics

Major primary sources to consult