Our Lady of Guadalupe (1531)

A civilisation marked by human sacrifice

When the apparitions occurred, central Mexico had just been conquered by Hernán Cortés (fall of Tenochtitlan on 13 August 1521, ten years earlier). Aztec civilisation practised human sacrifice on a large scale: Spanish chronicles describe ceremonies atop the Templo Mayor in which priests tore the still-beating heart from victims in honour of the sun god Huitzilopochtli. The exact number of victims per year remains debated (from a few thousand to several tens of thousands depending on the source), and these rites occupied a central place in the imperial cult. Added to this ritual violence was the trauma of the conquest: massive demographic collapse through epidemics, dispossession of the elites, and a difficult evangelisation carried out by a handful of Franciscans who landed in 1524 (the "Twelve").

Quetzalcóatl and the accounts of omens

The chronicles of the conquest link the arrival of the Spaniards to the expectation of the return of Quetzalcóatl, a figure at once divine and royal, associated with a departure toward the east. Juan de Torquemada thus reports that Moctezuma sent greetings to Cortés believing he recognised this return. This account, handed down after the conquest, sheds light on how the conquest was understood and retold; it does not give direct access to Moctezuma's intentions in 1519.^[6]

François Brune connects this expectation with the vision attributed to Princess Papantzin, sister of Moctezuma: returned from a state in which she had been thought dead, she is said to have announced ships bearing crosses and the arrival of preachers of the true God. Brune here follows Francis Johnston and Christian Duverger. This account belongs to the body of omens transmitted by the chroniclers; it provides a religious context for the apparitions, without constituting testimony about the events of Tepeyac themselves.^[7]

The principal historical source is the Nican Mopohua (in Nahuatl: "Here is recounted"), a text attributed to the indigenous scholar Antonio Valeriano (c. 1520–1605), educated at the Colegio de Santa Cruz de Tlatelolco where the Franciscans taught the Indian elite Latin, Spanish, and classical Nahuatl rhetoric^[8]. Composition in the mid-sixteenth century is defended by supporters of this attribution; the text was published in full for the first time by the priest Luis Laso de la Vega in the Huei Tlamahuiçoltica (Mexico City, 1649)^[9].

Saturday 9 December 1531 — the first apparition

The account begins on Saturday 9 December 1531. Juan Diego Cuauhtlatoatzin, 57 years old, a recently converted Indian peasant from Cuauhtitlán living at Tulpetlac^[10], is crossing the hill of Tepeyac on foot on his way, as twice a week, to the Franciscan mission of Tlatelolco — about fifteen kilometres each way. The Nican Mopohua reports that he suddenly hears a singing of birds "more beautiful than any he had ever heard" coming from the top of the hill, then silence, then a very gentle voice calling him by his diminutive: "Juanito, Juan Dieguito!" — the familiar Nahuatl usage^[11].

Juan Diego climbs the hill and sees a young woman "of great beauty" whose garments shine like the sun. She speaks to him in his mother tongue, Nahuatl, and introduces herself:

"I am the perfect and ever Virgin Holy Mary, Mother of the truest God." — Nican Mopohua, words of the Virgin to Juan Diego, 9 December 1531^[12]

She asks him to go and find the bishop of Mexico, Juan de Zumárraga, OFM, so that he may have a church built on this spot — "there where she will be able to hear men's weeping, their sorrow, care for them and heal all their pains". Juan Diego sets off at once.

The Virgin then reveals the very meaning of her apparition at Tepeyac, in words of shattering significance for the Nahua people:

"I am truly your compassionate Mother, yours and that of all of you who are one in this land… There, I shall hear their weeping and their sorrow, to care for them, to heal all their pains, their miseries, their sufferings." — Nican Mopohua, words of the Virgin to Juan Diego, 9 December 1531^[13]

These words — "truly your Mother" — strike at the heart of a people traumatised by human sacrifice, epidemics, and the collapse of their empire. The Virgin does not merely appear: she declares herself universal mother of a people hitherto despised by their own gods, and healing mother of a humanity covered with wounds.

The bishop's first refusal

The episcopal palace of Mexico City stands near the former Templo Mayor. Zumárraga, the first bishop of Mexico, does not speak Nahuatl; an interpreter, Juan González, acts as intermediary. The bishop listens to the account with courteous scepticism, dismisses him without following up at once, and asks Juan Diego to come back another time. Juan Diego leaves, deeply disappointed: he understood full well that Zumárraga did not believe a word of his account.

Returning to Tepeyac at nightfall, the Lady appears to him again. Juan Diego prostrates himself and suggests she send instead someone nobler, more respected, for he is himself only "a country man", "the least of the village". The Lady replies:

"It is absolutely necessary that it be you, personally, who go and ask […] and I order you to go again tomorrow to see the bishop." — Nican Mopohua, words of the Virgin to Juan Diego, 9 December 1531 (evening)^[14]

The requested sign — Castilian roses in midwinter

The next day (Sunday 10 December), Juan Diego returns to see Zumárraga. This time the bishop listens to him at greater length, scrutinises him, and asks him to come back with a sign proving the authenticity of the vision. On Monday 11 December, Juan Diego cannot go: his uncle Juan Bernardino is gravely ill. On Tuesday 12 December 1531, Juan Diego goes to fetch a priest for extreme unction, but avoids the hill so as not to be delayed. The Virgin appears to him nonetheless, reassures him about his uncle's recovery, and asks him to climb to the top of the hill to gather all the flowers he finds there.

"Am I not here, I, your mother? Are you not under my shadow and my protection? Am I not the source of your joy?" — Nican Mopohua, words of 12 December, translation by François Brune, p. 243.^[15]

Yet in December, at 2,250 m altitude, on a rocky hill, in this freezing season, the account describes stones and thorny plants. Juan Diego climbs up all the same and finds, "filled with admiration", a bed of Castilian roses — flowers the account contrasts with the cold and barrenness of the hill — blooming in full winter flower. He gathers them, brings them back to the Virgin, who herself arranges them in the hollow of his tilma, saying to him:

"My son, the littlest one, these varied flowers are the proof, the sign that you will carry to the bishop." — Nican Mopohua, words of the Virgin to Juan Diego, 12 December 1531^[16]

The revelation to Zumárraga and the imprinting of the image

Juan Diego returns to the episcopal palace, tells the whole story again, and unfolds his cloak. The roses fall to the ground — and the bishop in turn falls to his knees: imprinted on the tilma is the image of the Virgin, hands joined, head gently inclined. Zumárraga immediately keeps the cloak (Juan Diego leaves without it), and has a first small chapel built at the foot of Tepeyac, on the spot indicated by the Virgin.^[17] Joachim Bouflet notes one detail of this audience: the Castilian roses first move Zumárraga, himself of Spanish origin, before the miraculous imprint overwhelms him.^[18]

Antonio Valeriano and the transmission of the account

The Nican Mopohua is written in classical Nahuatl of exceptional rhetorical quality: the text employs the stylistic devices proper to Aztec rhetoric (parallelisms, diphrasisms, floral metaphors), which bear witness to its rootedness in Nahua culture. Antonio Valeriano (c. 1520–1605), born in Azcapotzalco, belongs to the first generation of Indians educated at the Colegio de Santa Cruz de Tlatelolco founded in 1536; he later teaches there, holds indigenous government offices in Mexico City, and translates part of the famous Códice Florentino for the Franciscan Bernardino de Sahagún. His collaboration with Sahagún and his knowledge of indigenous culture lend weight to the traditional attribution. An encounter with Juan Diego remains chronologically possible, but is not attested by any surviving direct testimony.^[19][20]

The archives of the early cult

The early documentation includes narrative texts, Nahuatl poems, and administrative acts. The latter have particular value: a benefice or a capitular decision situates the sanctuary's existence in everyday life, independently of any apologetic account. Brune counts 40 registers relating to the sixteenth century, 27 of which concern the hermitage, often regarding its orphanage.^[21]

• In 1562, a benefice of 100 pesos is assigned to the hermitage on the houses of Martín de Aranguren, Zumárraga's majordomo.^[22]
• The capitular decisions of 14 September 1568 and 6 September 1569 regulate the absence of canons who leave the cathedral to celebrate the Nativity of Mary at Guadalupe.^[23]
• The Pregón del Atabal, a Nahuatl song preserved in the Cantares Mexicanos, belongs to the poetic reception of the Virgin; its dating and the interpretation of its allusions must be distinguished from those of administrative acts.^[24]
• The Nahuatl text Inin huey tlamahuiçoltzin, dated around 1570 by the studies reported by Brune, expressly mentions the miraculous image on the poor man's tilma. Its transcription and Spanish translation were published by Xavier Noguez.^[25]

The 1548 Codex Escalada

The Codex Escalada, rediscovered in 1995, is a hide 20 × 13.3 cm bearing the date 1548, scenes of apparition, Nahuatl inscriptions, and a signature attributed to Bernardino de Sahagún. Brune details the examinations undertaken after the agreement of 30 January 1996 with the Institute of Physics: microscopic, infrared, and ultraviolet photographs, X-rays, and elemental analysis of the inks. Over thirteen zones, the PIXE method — detection of X-rays emitted under proton bombardment — distinguishes the elements present. Calcium is linked to tanning; sulphur and chlorine are also abundant.^[26]

The expert assessment of the signature is distinct from that of the medium. In a letter of 12 June 1996, Charles E. Dibble, a Sahagún specialist, recognises it as authentic and compares it with signatures dated between 1550 and 1560; a second expert opinion requested from a laboratory working for the Bank of Mexico concludes likewise. The inscribed date, the material antiquity, and the palaeographic dating are therefore not three identical measurements. These examinations support the authenticity defended by Escalada; they do not constitute radiocarbon dating of the parchment.^[27]

Answer to the sceptical academic objection (Stafford Poole, Edmundo O'Gorman)

The principal modern academic objection, formulated notably by Stafford Poole CM in Our Lady of Guadalupe: The Origins and Sources of a Mexican National Symbol, 1531–1797 (University of Arizona Press, 1995)^[28], holds that the absence of any clear mention of the apparitions in Spanish sources prior to 1648 makes a late elaboration probable: the account, unknown before Miguel Sánchez's 1648 publication, is said to have taken written form in the mid-seventeenth century, on the model of pious peninsular Marian legends imported by the missionaries. The position of Edmundo O'Gorman in Destierro de sombras (UNAM, 1986)^[29] is distinct: he attributes the Nican Mopohua to Antonio Valeriano and fixes its composition after 1556 (chapter III) — nearly a century before Luis Laso de la Vega's Huei Tlamahuiçoltica (1649).

Against this reading, defenders of the Guadalupan tradition set several documentary pieces, notably those studied by Eduardo Chávez Sánchez, postulator of the Juan Diego cause, and Xavier Escalada SJ:

1. The anti-Guadalupan sermon of Fray Francisco de Bustamante (8 September 1556). The Franciscan provincial publicly attacks the cult paid to "this image painted yesterday by an Indian" and calls for its real authors to be sought out. The inquiry (Información of 1556) triggered by Archbishop Alonso de Montúfar is entirely preserved^[30]: it proves, 93 years before the Huei Tlamahuiçoltica, that the cult of Guadalupe at Tepeyac was public, popular, and controversial in 1556 — less than twenty-five years after the events.
2. The Codex Escalada (1548). A document bearing the date 1548, subjected to examinations of its medium and inks and to expert assessment of the signature attributed to Sahagún; its drawings depict Juan Diego and the Virgin^[31].
3. The sixteenth-century Nahuatl poems. The Pregón del Atabal and the text Inin huey tlamahuiçoltzin bear witness to the indigenous reception; the second explicitly mentions the image on the tilma^[32].
4. The Nican Mopohua itself as a linguistic document. Its classical Nahuatl — rhetorical figures of Aztec poetry, ritual parallelisms, coded floral metaphors — attests a literary work rooted in Nahua forms; specialists Miguel León-Portilla and Mario Rojas Sánchez studied this rootedness and its connection with a sixteenth-century composition^[33].
5. The basilica's material archives. Of the 40 registers preserved relating to the sixteenth century, 27 directly concern the Tepeyac hermitage^[34]. The acts of Mexico City's cathedral chapter, from 14 September 1568 onward, had to regulate the absences of canons who left to celebrate Guadalupe rather than attend the office — testimony to the sanctuary's attendance thirty-seven years after the events^[35].

A real silence, but one that does not close the debate. Brune acknowledges the silence of several official documents close to 1531–1533. Two questions remain distinct: the existence of an early cult at Tepeyac, attested notably in 1556, and the transmission of the detailed account of the apparitions. Poole and O'Gorman discuss mainly the second and the genesis of the cult; their position does not consist in denying any sanctuary before 1648. In response, defenders of Guadalupe bring together Nahua tradition, sixteenth-century documents, and the memory gathered by ecclesiastical inquiries.^[36][37][38]

The 1666 inquiry: a family memory questioned

The Informaciones of 1666 no longer gather eyewitnesses of 1531. They question twenty deponents — eight witnesses from Cuauhtitlán and twelve Spaniards — on the memory received from their parents or grandparents. The Cuauhtitlán group includes seven Indians and one mestizo, Marcos Pacheco; it counts two women, Juana de la Concepción (85) and Catharina Monica (100). The youngest of the eight is 78 (Pablo Xuarez), while Andrés Juan declares 112 to 115 years, an age Brune himself recognises as problematic. Their interest lies in the named chains of transmission, the antiquity of local devotion, and the comparison of answers.^[39]

Brune notes one precise result concerning these eight Indian witnesses: none of them gives the bishop's name — with the partial exception of Juan Xuarez, who designates the first bishop as "that brother So-and-so of Zumárraga" — and none expressly confirms 12 December, although the questionnaire suggests this information.^[40] Conversely, details that were not asked for appear. The answers are therefore not a mere uniform repetition of the questions. The examinations of painters and physicians conducted during the same inquiry form a second, material part, independent of the age of family memories.^[41]

An extremely perishable plant medium

The tilma is formed of two widths joined by a vertical seam. Brune reports measurements of 166 to 168 cm in height and 103 to 105 cm in width, along with an early reduction of its upper part to fit the frame. These are the dimensions of the preserved object, not a certain measurement of the cloak as worn in 1531.^[42]

The botanist Isaac Ochoterena, founder of the UNAM Institute of Biology, identified the fibres as maguey ixtle, that is, an agave fibre. Brune transmits the designation "agave potule zacc". This coarse plant medium is vulnerable to humidity, friction, and fibre deterioration; its lifespan depends, however, on the weave, the treatments, and the environment. The experiment of José Ignacio Bartolache provides here a more precise historical comparison than a universal lifespan attributed to all agave cloths.^[43][44]

The Bartolache counter-test (1785–1796) — a copy without primer put to the test

Convinced that only direct material comparison could settle the debate on preservation, Bartolache publicly announced his project on 27 December 1785, then examined the original on 29 December 1786. He had four ayates made and entrusted two copies without primer to the painters Andrés López and Rafael Gutiérrez. The second was installed in the chapel of El Pocito, at the foot of Tepeyac, on 12 September 1789, then removed on 8 June 1796 — less than seven years later. The witness Francisco Sedano records the condition of the removed copy:

"The turquoise blue has turned dark green, ashen and as if mouldy; the gold is tarnished and has fallen off in places; the pink colour is completely gone, turning white; […] the carmine has blackened; the paint has paled completely and fallen off in places, uncovering the threads of the cloth, some of which are breaking." — Francisco Sedano, testimony on the Pocito copy, quoted by François Brune^[45]

This is the most conclusive material comparison in the case: a copy on the same type of medium, without undercoat, exposed in an environment close to that of the sanctuary, visibly deteriorated in less than seven years — even though Bartolache himself admits he did not manage to match the fineness of the original. The original, for its part, has crossed five centuries.

Five centuries of manual wear, unglazed for 116 years

As early as 1666, a medical inquiry ordered for the Guadalupan canonical cause describes a sanctuary built near a lagoon and marshes, in lastingly humid air; the report of Dr Juan de Melgarejo, dated 28 March 1666, concludes that there can be, in such an environment, no natural cause for the cloth's preservation^[46]. For the first 116 years (1531–1647), the image was exposed with no protection at all to the veneration of the faithful. The painter Miguel Cabrera in the eighteenth century reports that, even after the installation of a first two-piece glass pane in 1647, it was regularly opened to allow the faithful to bring devotional objects (medals, rosaries) close: according to his testimony transmitted by Brune, these openings, without being daily, were repeated a great many times over more than two hundred years^[47]. He describes in particular what he saw in 1753:

"On a single occasion, in 1753, when I was present, […] five hundred images passed before my eyes which touched the cloth; then various ecclesiastical personages of quality spent more than two hours in this pious exercise." — Miguel Cabrera, testimony on contacts with the tilma (the first sentence summarises the passage transmitted by Brune; the quotation reproduces the 1753 account)^[48]

The repeated contacts documented by Cabrera make the preservation all the more remarkable. They do not mean that every part of the image crossed the centuries unaltered: observations of retouching and peripheral wear belong to the same material record.^[49][50]

Exposure to candles and the preservation of colours

Callahan connects the freshness of the blue and pink with the ancient exposure to candles, light, and humidity variations. Brune reports a measurement of over 600 microwatts for a candle, without specifying in this passage the receiving surface, the distance, or the spectral band. This value therefore does not allow a dose received by the tilma over the centuries to be calculated, nor the result to be simply multiplied by the number of candles. The preservation argument rests first on the condition of the observed zones and on the documented history of their exposure.^[51]

The nitric acid incident (1791)

Brune reports that in 1791, during cleaning of the silver frame, a mixture of nitric acid and water accidentally ran onto the cloth. He describes a yellowish stain, without perforation, and reports that it faded with time. This accident belongs to the history of preservation: the stain is a localised alteration, distinct from the preservation of the principal figure.^[52]

The bomb attack of 14 November 1921

On 14 November 1921 at 10:30 in the morning, a worker named Luciano Pérez, later identified by archdiocesan accounts as an employee of the Presidency's private secretariat, placed a bouquet of flowers before the altar on which the tilma was displayed. He calmly walked out, and a few minutes later, a violent explosion shook the building. The bouquet contained a bomb. The damage was enormous: the marble altar steps were blown apart, the candlesticks, vases, church windows, and even those of neighbouring houses shattered. A heavy metal crucifix was completely bent backwards by the blast — it is kept today in the basilica under the name of the "Santo Cristo del Atentado" (the Holy Christ of the Attack).

But the tilma remained intact behind its glass. The contrast between the documented blast (altar, liturgical objects, and windows damaged) and the total preservation of the image continues to intrigue investigators^[53].

1936 — Nobel laureate Richard Kuhn

Brune reports that at the beginning of 1936, Ernesto Sodi Pallarés had Fritz Hahn transmit to the German chemist Richard Kuhn two coloured fibres, one red and one yellow, from the tilma. The conclusion attributed to this analysis is:

"On these two fibres, one red and one yellow, there is no colouring matter of vegetable, animal, or mineral origin." — Conclusion attributed to Richard Kuhn, reported by François Brune^[54]

This three-origin classification describes the transmitted conclusion; it does not by itself constitute an analytical inventory of the substances investigated. Richard Kuhn — 1938 Nobel laureate in chemistry (received in 1939) for his work on carotenoids and vitamins — stood at the summit of world chemistry at the time of the report. But Brune reproduces no complete protocol of this analysis: on this precise point, François Brune himself is clear — "we have only his conclusions"^[55]. The 1936 result must therefore be cited as a reported historical conclusion, not as a reproducible experiment. The infrared analyses conducted in 1979 by Callahan, bearing on other zones and another question (the optical behaviour of pigments, not their chemical composition), shed light on the case without reconstructing Kuhn's protocol or examining the same two fibres.

1979 — Callahan and Smith, infrared photography

On 7 May 1979, two American researchers, Philip Serna Callahan (biophysicist at the University of Florida, expert in infrared photography) and Jody Brant Smith (professor of aesthetics and philosophy at Pensacola College, Florida) received the exceptional authorisation to photograph the tilma at very high resolution, in infrared photography. The conclusions of the examination were published in March 1981 in Callahan's now-classic study: The Tilma under Infrared Radiation (CARA Studies in Popular Devotion, vol. II, no. III, Washington D.C., 45 pp.)^[56], and taken up with further development in Smith's book The Image of Guadalupe — Myth or Miracle? (Doubleday, 1983), who had taken part in the examinations without being a catalogued co-author of the CARA report.

In the zones of the principal figure which they distinguish from the retouched secondary parts, the two researchers report:

1. No brushstroke, primer, or preliminary sketch detected in the central zones examined.
2. No cracking comparable to the network the authors looked for on the central zones, despite their age.
3. The blue of the mantle: of an even, unfaded intensity, "a semi-transparent blue pigment, unknown… as bright as if it had been applied last week". The property of "semi-permanent" blue, subject to fading with time, concerns on the contrary the comparison blues (copper oxides of Maya frescoes and Mixtec manuscripts), with which Brune contrasts the blue observed on the tilma.^[57]
4. The pink of the robe is described by Callahan as physically inexplicable:

"The robe intensely reflects visible radiation, but remains transparent to infrared rays… Of all the pigments studied, the pink is by far the most transparent… It is unlikely to be cinnabar or haematite, which are both red pigments of India. Nor is it an orange mineral (too yellow), for all these minerals are opaque and not transparent to infrared. Red lead may be excluded for the same reason. Red oxide is an absolutely permanent pigment… it would be a likely candidate were it not also completely opaque to infrared. This leaves only modern aniline reds. Yet nowhere in this picture are modern aniline colours to be found… It is ultimately inexplicable." — Philip Serna Callahan, quoted in Jody Brant Smith, The Image of Guadalupe — Myth or Miracle?, Doubleday, 1983, pp. 98–99^[58]

Callahan also observes that certain natural defects of the weave contribute to the modelling of the face: "A coarse fibre of the cloth rises a little above the level of the rest of the canvas and follows exactly the upper edge of the lip. The same awkward imperfection is found under the lighted part of the left cheek and under the right eye."^[59] A painter deliberately exploiting the raw relief of the weave to build modelling is an extremely difficult technical hypothesis to execute with the naked eye on so rough a canvas.

A stratified image: the principal without brushwork, secondary additions repainted

The absence of brushstrokes and primer holds, in Callahan's analyses, only for the principal figure — face, hands, robe, mantle. The same researcher notes, on several secondary elements of the composition (golden rays, lunar crescent, angel, certain stars and borders), a different picture:

"In certain places corresponding to these additions, a primer can be discerned, clumsy but real, and brushstrokes, whereas these are completely absent from the original parts." — François Brune, in his exposition of Callahan's observations (sentence written by Brune himself, p. 36)^[60]

Brune stresses the distinction between the image and its repaints: "This does not exclude that a few detailed retouchings, more precisely repaints, may have been carried out where the weather and above all the devotion of the faithful had begun to cause damage."^[61] Ancient testimonies point the same way: as early as 1666, then again under Cabrera's pen in the eighteenth century, several peripheral elements of the image are already described as retouched. The scientific enigma therefore does not concern "the image" taken globally, but very precisely the central figure: on these zones, Callahan detects neither preparatory sketch nor brush trace under his examination conditions.^[62]

The ancient argument of the reverse side

The absence of primer rests not only on the 1979 photographs. Cabrera takes up the depositions of the painters consulted in 1666: they say they see the image's colours on the back of the cloth. An opaque preparation layer would, in their view, have prevented this visibility. Their reasoning thus bears on a precise material property: the passage of colours through the cloth.^[63]

"On the back of the cloth the whole Holy Image can be seen, with all its colours, those admired on the front." — Depositions of the painters of 1666, reported by Miguel Cabrera and quoted by François Brune.^[64]

This ancient testimony and the infrared examination employ two different means to look for pictorial preparation. Bringing them together strengthens the interest of the finding, while leaving room for the local primers detected on certain ornaments. The absence of visible sketch is an observational result; it does not by itself exclude every human pictorial technique.^[65]

The attribution to a painter named Marcos

The oldest objection against the miraculous origin of the image goes back to 1556. The Franciscan provincial Francisco de Bustamante, in a sermon delivered on 8 September in Mexico City, denounces the cult paid to "this image painted yesterday by an Indian" and names this painter: a certain Marcos^[66]. Some modern researchers have proposed identifying this Marcos with the indigenous painter Marcos Cipac de Aquino, active in Mexico City in the mid-sixteenth century — but Brune reminds us bluntly: "no one has ever proved it"^[67], and no work certainly attributed to this painter has ever been technically compared with the tilma.

The objection deserves to be taken seriously rather than swept aside: it is contemporary with the events, publicly raised by a leading ecclesiastical authority, before the highest civil and religious authorities of the country — the archbishop opening an inquiry the day after the sermon. But the answer cannot be a simple denial of the attribution — it must rest on the differentiated material analysis set out above. That a craftsman named Marcos may have executed retouchings, a decorative frame, or a distinct work is historically plausible and nothing implausible for sixteenth-century Mexico; it does not, however, explain the absence of any detectable preparatory tracing, pentimento, or brushstroke on the central figure itself, as documented by the examinations of 1666, Cabrera, and Callahan.

Chromatic variations and the diffraction hypothesis

Brune reports photographic tests carried out in 1947 at distances ranging from a few centimetres to three metres: the face appears pinkish-grey up close and greenish-grey from further away. Callahan connects these variations with diffusion or diffraction effects, comparable in principle to those he studied on bird feathers and butterfly scales. The observation concerns the rendering of light by the surface; it does not demonstrate any luminous emission proper to the image.^[68]

The physicist Éric de Bazelaire in turn proposes an explanation by diffraction. To decide between possible causes, lighting geometry, distance, photographic response, and surface properties would have to be connected. The analogy with a "hologram" remains a way of describing astonishment at the effect: no holographic recording of the cloth is established by these observations.^[69]

Rumours to be explicitly set aside

Several widely circulating claims on the Internet must be clearly distinguished from the serious scientific record. The Mexican researchers met by François Brune in Mexico City in February 2008 refused to endorse three "discoveries" with no published protocol: a beating heart at 115 beats per minute, a skin temperature of 36.6 °C, and an image floating 0.3 mm above the cloth. Brune reports their concern that "fanciful inventions by amateurs might discredit the real scientific discoveries already made"^[70]. Likewise, the interpretation of a luminous spot photographed on the Virgin's belly as the silhouette of an embryo does not convince Brune himself, who judges that "it takes a great deal of goodwill"^[71]. These claims are not part of the results of the examinations described above.

The eyes of the image offer two successive bodies of evidence. Between 1956 and 1976, ten physicians describe a human bust in both eyes and optical effects giving an impression of depth. From 1979 onward, José Aste Tonsmann undertakes a more detailed digital reading, eventually proposing thirteen silhouettes. The irises measure only 7 to 8 millimetres: the scale of the photographs and the method of interpretation are therefore decisive for understanding these observations.^[72][73]

1929 — Alfonso Marcué and the first bearded man

In 1929, the professional photographer Alfonso Marcué González is invited to the basilica to photograph the tilma. Enlarging a negative of the face at home, he discovers in the right eye the reflection of a bearded man. At the time, the observation passes almost unnoticed.

1951 — J. Carlos Salinas Chávez confirms

On 29 May 1951, the draughtsman J. Carlos Salinas Chávez, examining an enlarged photograph with a magnifying glass, finds the same bearded man again in the right eye — and notes that he is also present in the left eye, but slightly offset. This time the observation causes a stir, and the Catholic authorities of Mexico City decide to authorise a methodical scientific inquiry.

1956–1976 — The cohort of ophthalmologists

Some ten Mexican ophthalmologists successively examine the eyes of the tilma. Brune reproduces, after Jorge A. Escalante Padilla ("Los ojos de la imagen de la Virgen de Guadalupe"), the list of experts requested by the ecclesiastical commission: the dates below are those of the requests, not those of dated reports. They are to be distinguished from Torija Lavoignet's detailed report of 20 September 1958, quoted below.^[74]

According to Escalante Padilla's synthesis transmitted by Brune, all the written reports submitted by these requested physicians conclude with the recognition of the same finding: the presence of the reflection of a bearded man's bust, corresponding to the first Purkinje-Sanson image.^[75]

The convergence reported by Escalante Padilla concerns one precise point: the presence, in both eyes, of the reflection of a bearded man's bust corresponding to the first Purkinje-Sanson image^[76]. It is this convergence — ten physicians, over twenty years, on the same circumscribed finding, as transmitted by the cited synthesis — that forms the robust foundation of the case; it must not be confused with the broader and more debated set of thirteen silhouettes, which belongs to later and distinct work (see below). Neither this list nor this convergence documents by itself the methodological independence of the examinations or the consultation of the ten original reports. More surprising still: Dr Jorge Escalante Padilla reports the presence of a microscopic venous network on the eyelids and cornea of the eyes — a report transmitted by a secondary source, with no experimental protocol reproduced by Brune; it does not allow biological vessels to be identified on the image.

The Purkinje-Sanson law applied to the image

Purkinje-Sanson images are reflections produced by the optical surfaces of the eye. Modern nomenclature distinguishes four of them: the anterior and posterior faces of the cornea (P1 and P2), then of the crystalline lens (P3 and P4). P2 largely overlaps P1, hence the classic description of three discernible images. These reflections can also be reproduced on an artificial eye: their formation does not require a living organism^[77]. In the Guadalupan case, the physicians relate the shapes depicted on the tilma to this optical geometry; the "three reflections" mentioned below use their historical terminology.

The first of these three reflections — the corneal distortion of the bearded bust — is the one the cohort of ten physicians attests in both eyes, with a position offset in the left eye relative to the right eye, consistent with what binocular vision requires. The two additional reflections (posterior then anterior face of the crystalline lens), in contrast, are not reported with the same unanimity: the most detailed report, Dr Torija Lavoignet's, explicitly states that he did not observe them in the left eye (see below). The common agreement concerns the first reflection; it does not extend to all three reflections in each of the two eyes.

The ophthalmoscopic effect described by Torija Lavoignet

Torija describes to Brother Bruno Bonnet-Eymard the effect observed on 23 July 1956 under ophthalmoscope lighting. This testimony is distinct from his detailed report of 20 September 1958:

"When the light of the ophthalmoscope is directed onto the pupil of a human eye, a luminous reflection is seen shining on the outer circle of the pupil… Directing the light of the ophthalmoscope onto the pupil of the eye of the Image of the Virgin, the same luminous reflection appears. And as a result of this reflection, the pupil lights up diffusely, giving the impression of hollow relief… This reflection is impossible to obtain on a flat and, what is more, opaque surface… I subsequently examined with the ophthalmoscope the eyes in various oil paintings, watercolours, and photographs. On none of them, all of distinct persons, was the slightest reflection to be seen. Whereas the eyes of the Holy Virgin of Guadalupe give an impression of life." — Dr Rafael Torija Lavoignet, testimony gathered by Bruno Bonnet-Eymard, quoted by François Brune.^[78]

Dr Rafael Estartus Tobella completes the observation: "When the light of an ophthalmoscope is projected onto the front part of the eye, the iris shines more than the rest, not the pupil, which gives a sensation of depth; with, in addition, an impression as if the iris were about to contract at any moment."^[79] — an optical impression reported under the instrument's lighting, not a real biological contraction of the painted iris.

What Torija Lavoignet does not observe in the left eye

Torija actually carries out five successive examinations, between July 1956 and May 1958, two of them without the protective glass. On the right eye, he concludes unambiguously in favour of the three expected reflections, even specifying that "the shoulder and arm of the reflected man's bust extend beyond the circle of the pupil, producing a stereoscopic effect"^[80]. But for the left eye, his wording is markedly more cautious:

"The corresponding reflection of the man's bust is perceived fairly clearly, but […] the luminous reflections corresponding to the other two Purkinje-Sanson images are not observed." — Dr Rafael Torija Lavoignet, report of 20 September 1958, point 10 (text reproduced by Brune, with reference to Benítez)^[81]

Dr Javier Torroella Bueno, in his report of 26 May 1956, prior to Torija's detailed report of September 1958, proposes a geometric explanation for this difference between the two eyes rather than a refutation of the observation:

"The figure of the left eye is not seen as clearly because, if it is seen clearly in the right eye, it is because it was situated 35 or 40 cm from that eye and, by that very fact, the left eye was a few centimetres further away, which sufficed for it to be out of focus and become blurred." — Dr Javier Torroella Bueno, quoted by Carlos Salinas, Descubrimiento de un busto humano en los ojos de la Virgen de Guadalupe, Editorial Tradición, 1999, p. 27^[82]

The difference between finding and explanation is precise here: it is not "each ophthalmologist" who identified "the three reflections in both eyes", but a broad agreement on the first reflection, completed by a plausible optical explanation — not by additional direct observation — for the other two in the left eye.

1979–1997 — José Aste Tonsmann and the 13 silhouettes

Dr José Aste Tonsmann, Peruvian engineer and doctorate holder in computer systems, a specialist in digital image processing, undertakes from 1979 onward a series of studies continuing until 1997, in two campaigns (1979–1982, then 1987–1997)^[83]. Thanks to digital enlargement techniques progressing to a factor of 2,000 times, he identifies in the corneal, iris, and pupil zones of both eyes thirteen persons, according to his interpretation of the enlargements, forming what resembles the scene present when Juan Diego opened his tilma before the bishop:

• An Indian in sandals with an earring (measurable strap width: 12 hundredths of a millimetre) — probably a servant of the bishop.
• An old bearded man, bald with a tonsure, straight nose, hollow cheek, tear at the corner of the lips, white beard — Bishop Juan de Zumárraga (the physical correspondence with the portrait painted by Miguel Cabrera is striking).
• A young man (spotted in the left eye), distinct from the next person.
• An Indian wearing the tilma knotted at the neck, crowned with a pointed hat (the cucurucho) — probably Juan Diego unfolding his cloak, according to Tonsmann's proposed identification.
• A Black woman (0.7 mm in the left eye) — see below.
• A complete family group: woman with baby on her back, man in sombrero, children — the only ensemble Tonsmann explicitly places on the pupil itself, distinct from the rest, at a different scale. The other silhouettes are described in the corneal and iris zones, not on the pupil.

The protocol is described in two stages. The photographs, taken directly from the original and most often without glass, are first digitised on a microdensitometer with a grid of 25 down to 6 micrometres on the photograph. The step depends on the prior enlargement: it does not automatically designate the size of the detail resolved on the tilma. Brune separately mentions a colour scanner of 1,200 dots per inch for the reconstruction, as well as enlargements of 32 to 2,000 times. An enlargement makes visible information already recorded; it does not add details absent from the negative.^[84]

To test his identifications, Tonsmann seeks the corresponding position in the other eye. To Brune, who questions him, he explains what convinces him these are not mere spots:

"Finding the corresponding reflection in the other eye, in the place it should normally occupy according to the laws of optics and with the distortions normal to this second position." — José Aste Tonsmann, interview reported by François Brune, p. 58.^[85]

This bilateral correspondence is Tonsmann's central argument, but it rests on an interpretive identification of microscopic shapes by a single researcher, over nearly twenty years of work — a different evidential status from the more direct one of the ten medical reports on the corneal bust alone. Two levels are thus distinguished: the corneal reflection of the bearded bust, a finding transmitted by Escalante Padilla's synthesis for the ten requested physicians; and the thirteen silhouettes, the product of digital processing by a single researcher, later and more open to discussion.

The Black woman and Zumárraga's slave

The proposed identification of a Black woman among the silhouettes first surprised Tonsmann, who was then unaware of the African presence in the Mexico of that time. Historical research provided the answer. Hernán Cortés had brought Black slaves to Mexico. Father Mariano Cuevas SJ, in his Historia de la Iglesia en México (Mexico City, 1921–1928), found Bishop Zumárraga's will by which the bishop granted freedom to a Black slave in his service:

Zumárraga's will grants freedom to a Black slave who had served him in Mexico City. Tonsmann discovers this document while reading Mariano Cuevas's Historia de la Iglesia en México. — Document reported by François Brune, p. 58.^[86]

The will attests the presence of African persons in the bishop's household and makes the proposed identification historically possible. It proves, however, neither María's presence at the presentation of the tilma in 1531, nor her identification in the photographic shape. The archive document and Tonsmann's reading corroborate each other on the context, without substituting for one another.^[87]

The family group on the pupil — a message?

The family group (woman, baby, man, children) presents two notable singularities: it is not at the same scale as the other persons, and it lies on the pupil itself (not on the iris). Tonsmann lends a symbolic significance to this placement: he sees in it the family the Virgin would be looking at — perhaps the emblem of entire humanity called to come to her, which Tonsmann interpreted as a possible "hidden message to be deciphered".

Perspective inconsistencies, an objection not to be evaded

Brune notes in Tonsmann's reconstruction perspective anomalies that the scene fails to unify:

"Some appear in the foreground but much smaller than the others, whereas the normal laws of perspective should make them appear slightly larger. Bishop Zumárraga's head is far too large compared with the Indian seated right beside him." — François Brune, on Tonsmann's inventory^[88]

The family group, in particular, poses a difficulty that enthusiastic summaries sometimes pass over in silence:

"This group is not at the same scale as the other persons. […] their arrangement as well as their attitude seems without any relation to the scene of Juan Diego's visit to the bishop." — François Brune^[89]

These reservations do not disqualify the whole ophthalmological record — the corneal reflection of the bearded bust remains attested by the medical reports as transmitted by Escalante Padilla's synthesis. But they forbid presenting the reading of the thirteen silhouettes as a scene entirely and uniformly reconstructed: it is a structured interpretation, with its strengths and its grey areas, not an accomplished fact.

46 stars arranged 23 + 23

The Virgin's blue-green mantle bears 46 golden stars, distributed in two groups of 23. Their arrangement prompted comparison with the constellations of the Mexico City sky.^[90]

Hernández Illescas: reconstructing the sky then choosing a projection

Juan Homero Hernández Illescas and his collaborators compare the stars of the mantle with a reconstruction of the Mexico City sky on 12 December 1531. Brune describes recourse to the UNAM ephemeris department, to several charts, and to the Laplace observatory's Spitz Junior planetarium. The projection is traced by transparency from the other side of a glass wall, which reverses right and left. The researchers then use a convex aluminium surface to adapt the chart to the Virgin's silhouette: this geometric deformation is an anamorphosis.^[91]

This procedure is more elaborate than a simple superimposition of two drawings. It involves choices of projection, orientation, and compression of distances. East is placed at the top, west at the bottom; some constellations are incomplete because their other stars would fall outside the mantle. The proposed correspondence must be read with these transformations, which are part of the method.^[92]

The date and time adopted

Brune reports a reconstruction for 10:40 a.m., local time, which he connects with the winter solstice and the presumed moment when Juan Diego presents the flowers. The Nican Mopohua does not give this time to the minute. 12 December Julian corresponds to 22 December Gregorian for 1531: the proximity to the solstice illuminates the symbolic reading, but a computed celestial chart cannot by itself fix the historical hour of the apparition.^[93]

The projection is also extended over zones where no star is painted. In Brune's exposition, the Corona Borealis would correspond above the head, Virgo at the breast and joined hands, Leo at the belly. These central constellations are extensions of the model; they are not figures directly drawn on the tunic. The authors read in them Mary's royalty and Christ's presence.^[94]

Comparison with other starry images

Brune reports a counter-test on more than 150 Marian paintings of the seventeenth and eighteenth centuries: the authors say they recognised in none of them any grouping corresponding to a constellation. This comparison forms their argument against a merely decorative scattering. To give it statistical value, however, the matching rules, admitted deviations, authorised transformations would have to be specified, and exactly the same criteria applied to the control images. The record describes an interpreted correspondence, without establishing a quantified probability of supernatural origin.^[95]

The Nahui Ollin on the belly — a major Aztec symbol

On the Virgin's pink robe unfolds a four-petalled floral motif precisely placed on the belly — it is the Aztecs' Nahui Ollin, the stylised four-directional flower representing the four cardinal points, movement, and cosmic fullness. In the reading proposed by Hernández Illescas and Rojas, this motif placed on the belly means: this woman is pregnant and carries divinity. Added to this is the black sash knotted high on the waist, another traditional Aztec sign of pregnancy, and the loose black hair (married women wore their hair knotted; free hair signals a young woman).^[96]

The tepetl flowers and the map proposed by Mario Rojas

Brune attributes to Father Mario Rojas Sánchez the geographical reading of the tunic. The floral motifs are compared with the Nahuatl glyph tepetl, "mountain"; a nose-shaped ending, yacatl, would allow Tepeyacatl to be read. Rojas places the Nahui Ollin at Tepeyac and orients his map with east at the top, west at the bottom, north to the left and south to the right, according to the convention he adopts from the codices.^[97]

The proposed superimposition is at a scale of 1:1,000,000. Brune details its principal correspondences:

The white parts of certain motifs are interpreted as snow-capped summits. This reading thus combines a hypothesis of glyph decipherment, a reference point, and a cartographic orientation; the geographical names are not inscribed on the robe. It extends the Christian reading of the image as a message addressed to the Nahua people.^[98]

The researcher Fernando Ojeda Llanes pursued his investigation from an intuition: if the stars and flowers of the mantle are interpreted as an ordered ensemble, and if mathematics is intimately linked to music (the musical scale has been mathematically representable since Pythagorean antiquity), perhaps there is a musical logic in the arrangement of the tilma's symbols.

He then divided a golden rectangle superimposed on the tilma into 46 equidistant lines (as many as there are stars). Stars and flowers fell on these lines according to this grid, like notes on a staff. The horizontal distance between the symbols made it possible to establish tones and durations. The musician Alberto Aguilar Portillo then played the sequence: out came a coherent and harmonious melody in both reading directions, according to this model. The choice of transcription rules itself determines part of the musical result.

This discovery remains more recent and less established than the eyes or the constellations — it belongs more to symbolic interpretation than to strict scientific proof. It is mentioned here as an explored hypothesis, not as an established fact^[99].

The golden ratio, φ ≈ 1.6180339887, is the positive root of the equation x² = x + 1. Ojeda's symbolic studies connect the format and certain divisions of the image with this proportion.^[100]

The often-cited rounded dimensions, 1.70 × 1.05 m, give a ratio of about 1.619. This calculation is not exact measurement: Brune gives a height of between 166 and 168 cm and a width of between 103 and 105 cm, and reports an early trimming of the top. The closeness of a ratio obtained from rounded figures therefore does not prove that the cloth was designed according to φ. The comparison belongs to a reading of proportions, distinct from the physical examinations of the tilma.^[101]

The pastoral greatness of the image lies in its double language: at once classical Christian catechesis (the Virgin's humility, joined hands, stars, bearer angel) and an Aztec theological manifesto (each symbol refers to a precise element of pre-Hispanic mythology, while subordinating it to the Virgin).

The veiled sun — above the god Huitzilopochtli

The golden rays haloing the Virgin envelop the sun without completely hiding it: for the Aztecs, this meant that this woman stood before the sun god Huitzilopochtli (to whom human sacrifices were offered) without being destroyed by him — and therefore that she was superior to him.^[102]

The moon under her feet — the Woman of the Apocalypse

The half-moon under her feet belongs first to the iconography of the Woman of the Apocalypse (12:1), clothed with the sun, with the moon under her feet and a crown of stars. The comparison with Nahua symbols extends this Christian reading; the moon cannot without distinction be identified with Quetzalcóatl, associated notably with Venus. As for coatlaxopeuh, "she who crushes the serpent", Brune presents it as a phonetic hypothesis to explain the name Guadalupe, not as a demonstrated etymology.^[103]

The bearer angel — heaven and earth

The angel supports the Virgin and holds a fold of her mantle and tunic. In the explanation offered on the basilica's website, these two garments figure heaven and earth united in the image's message. The meaning of the whole is Christological: Mary carries the Saviour and presents Him to men.^[104]

Evangelisation had already begun before December 1531. A letter from Zumárraga to the Franciscan general chapter of Toulouse, dated 12 June 1531, announces more than a million baptised since the friars' arrival. Brune quotes it through Christian Duverger and the tradition preserved by Jerónimo de Mendieta. This datum prevents the first seven years of mission from being reduced to a few thousand baptisms.^[105]

For 1536, Motolinía estimates the total at over four million; after fifteen years of Franciscan presence, accounts advance six million. These are chroniclers' estimates, not uniform demographic records. They nevertheless testify to an exceptionally vast movement. Guadalupe's role belongs within this already-begun history: the Marian message touches peoples in their language and symbols, while missionaries multiply churches, schools, and hospitals.^[106][107]

At the Mexican census of 2020, 77.7% of the population declares itself Catholic. Guadalupe's radiance is also measured in pilgrimages: the Mexico City authorities report 12.3 million pilgrims welcomed (asistencia) from 6 to 12 December within the Operativo Basílica 2024. This total concerns the period covered by this operation; it does not represent as many people present simultaneously in the basilica.^[108][109]

Beatification of 6 May 1990

John Paul II beatified Juan Diego in Mexico on 6 May 1990; his liturgical memorial is celebrated on 9 December. The miracle retained for his canonisation concerns Juan José Barragán Silva, twenty years old, gravely injured after a fall on 3 May 1990. His mother invokes Juan Diego. Brune reports the testimony of the physician Juan Homero Hernández Illescas, who describes cranial and cervical lesions, then a spectacular improvement on 6 May, the day of the beatification.^[110]

Brune consulted with the physician the volumes of the inquiry, containing X-rays and expert assessments. He reports examination by several specialities and a comparison with nineteen fall cases. The medical conclusion on the healing and the ecclesial judgment on the intercession are two distinct stages of the process: it is this case that was retained for the 2002 canonisation.^[111]

Canonisation of 31 July 2002

On 31 July 2002, John Paul II celebrates in the basilica of Guadalupe the canonisation of Juan Diego, the first indigenous saint of the American continent. He stresses that his welcome of the Christian faith respected his indigenous identity and favoured the encounter of two worlds.^[112]

"The loving Mother full of compassion who leads to the true God." — John Paul II, homily for the canonisation of Juan Diego, 31 July 2002, § 5.^[113]

The principal stages of pontifical recognition

The principal stages of pontifical reception can be read as follows:

The recognition of the 1754 patronage comes with a proper office and Mass for 12 December. In Ecclesia in America (§ 11), signed in Mexico City on 22 January 1999, John Paul II welcomes the Synod Fathers' proposal "that 12 December be celebrated throughout the continent as the feast of Our Lady of Guadalupe, Mother and Evangeliser of America", and takes up her title of "Queen of all America". These acts concern the Church's worship and mission; they do not authenticate individually the physical or astronomical hypotheses about the image.^[117][118]

The following twelve points compose the convergence argument defended by Guadalupan authors. They bring together instrumental observations, reported historical conclusions, and interpretations: the table recalls their respective scope.

The golden ratio, the 1791 acid accident, and the 1921 attack complete these records. They must be examined with their own sources, like the analyses of the cloth and eyes presented above.

Convergence as argument

The strength of the Guadalupan case lies in bringing together a narrative tradition, a lasting ecclesial reception, and singular material observations. Not all data add up, however, as independent proofs: Tonsmann's identifications proceed from a single photographic series, and the astronomical, geographical, or musical readings involve interpretive choices. The Christian argument from convergence draws its force from the best-documented facts — preservation, differentiated examinations of surfaces, testimonies on the eyes, and the history of the cult — without requiring every symbolic hypothesis to be demonstrated.

"It is impossible to explain by natural processes the presence of the tiny portraits. Consequently, accepting the imprinting of the image of the Virgin of Guadalupe as a supernatural fact, I dare maintain that when Juan Diego was received, the Virgin Mary was present, invisible to the eyes of those who were there, but herself seeing the whole scene and, thereby, receiving in her eyes the reflected images of all those present, including Juan Diego himself. When he unfolded the tilma and the flowers fell, the image of Our Lady imprinted itself upon it, such as it was at that very instant — that is, bearing in her eyes the reflection of the whole group of persons witnessing this historic event. In this way, the Virgin Mary wished to leave us a snapshot of her miraculous imprinting on Juan Diego's ayate. […]" — Dr José Aste Tonsmann, El secreto de sus ojos, Lima, 1998^[119]

Sources shed light on different questions. The Guadalupe case is powerful precisely because it does not rest on a single isolated proof, but on a convergence: Nahuatl account, liturgical tradition, ecclesiastical inquiries, pontifical documents, material observations, chemical analyses, ophthalmological examinations, and astronomical studies.

Complementary articles

• The Holy Shroud of Turin: material examinations and the history of an exceptional image.
• The miracles of Lourdes: medical findings and ecclesial recognition of healings.
• Our Lady of Fatima: the account of the apparitions and the witnesses of 1917.
• Our Lady of Zeitoun: testimonies and photographic documentation.

Foundational works

• François Brune, La Vierge du Mexique ou le miracle le plus spectaculaire de Marie, Le Jardin des Livres, Paris, 2008, ISBN 978-2-914569-09-5. Record of fibres, early copies, analyses, and ocular observations, with references to the cited reports.

• Jody Brant Smith, The Image of Guadalupe — Myth or Miracle?, Doubleday, Garden City NY, 1983, xiv + 173 pp. + plates, ISBN 0385159714. Accessible presentation of the 1979 analyses.

• Philip Serna Callahan, The Tilma under Infrared Radiation, CARA Studies in Popular Devotion, vol. II, no. III, Washington D.C., March 1981, 45 pp. Reference technical study, catalogued under Callahan's name alone (Smith took part in the examinations and took up the case in his 1983 book).

• José Aste Tonsmann, Los ojos de la Virgen de Guadalupe, Editorial Diana, Mexico City, 1981 (protocol); El secreto de sus ojos, Tercer Milenio, Lima, 1998. 1979–1997 research on the 13 silhouettes of the eyes.

• Mariano Cuevas SJ, Historia de la Iglesia en México (5 vols.), 1921–1928. Historical source for Zumárraga's slave.

• Antonio Valeriano (traditional attribution), Nican Mopohua (Nahuatl text; Huei Tlamahuiçoltica edition, Mexico City, 1649). French translation in Brune, La Vierge du Mexique, appendix 5, pp. 237–246.

Catholic reference sources in French

• 1000 raisons de croire — articles 194 (the tilma) and 508 (the apparition), available on codexdei.mariedenazareth.com.
• Encyclopédie Mariale of the Marie de Nazareth association — Our Lady of Guadalupe / Scientific inquiry section.
• France-Catholique.fr — "Silhouettes in the pupils, constellations… What science says about Our Lady of Guadalupe".

Pontifical documents

• Brief Non est equidem of Benedict XIV, 25 May 1754.
• Homily of John Paul II for the canonisation of Juan Diego, basilica of Guadalupe, 31 July 2002 (full text on vatican.va).
• John Paul II, Ecclesia in America, 22 January 1999, § 11: Mary and the evangelisation of the continent.^[120]