Mark of Ephesus (1392-1444)

Birth and family in Constantinople

Mark was born in Constantinople around January 1392 under the baptismal name of Manuel Eugenikos^[4]. His father, George Eugenikos, held the office of sakellarios — an office of deacon-judge attached to the ecclesiastical court of Hagia Sophia, charged notably with the discipline of the clergy of the Great Church^[5]. His mother, named Maria, was the daughter of a physician. Manuel had a younger brother, John Eugenikos, who would in turn become a cleric, a poet and, after Mark's death, metropolitan of Selymbria; he composed the liturgical office in honour of his canonized brother^[6].

Their father died while Manuel was still a child, leaving his mother to organize her sons' education alone^[7]. It was a rare choice for the time: she placed Manuel under the direction of the best masters available in Constantinople, despite the family's financial straits and the dramatic shrinking of the Byzantine Empire, then reduced to its capital and a few enclaves.

An exceptional formation: Chortasmenos and Pletho

Manuel studied under the direction of two masters of the very first rank. The first, John Chortasmenos, was a renowned scholar, copyist and rhetorician of Constantinople, who would himself become a monk under the name of Ignatius and be raised to a metropolitan see^[8]. The second was George Gemistus Pletho (c. 1355-1452), a Neoplatonic philosopher of European renown, who initiated the young Manuel into mathematics and ancient philosophy^[9]. Pletho would himself accompany the Byzantine delegation to the Council of Florence a few years later, where his rediscovery of Plato lastingly marked the Florentine humanists and inspired the foundation of Marsilio Ficino's Platonic Academy^[10].

This double formation — rhetorical and philosophical — explains the technical competence Mark would later display before the Latin theologians: he was not a simple pious monk ill-prepared for scholastic debate, but a mind trained in the classical disciplines, capable of following a syllogistic reasoning down to its smallest presuppositions^[11]. Older Western historiography sometimes underestimated him on this point; recent scholarship insists on the contrary on his genuine theological competence, superior on certain points to that of several of his Latin opponents^[12].

Manuel himself became a teacher at the patriarchal school of Constantinople. But at twenty-six, in 1418, he abruptly renounced this career and his possessions^[13].

The renunciation: from professor to monk (1418)

In 1418, Manuel left Constantinople for the island of Antigone, one of the Princes' Islands at the entrance of the Gulf of Nicomedia, then under Byzantine administration^[14]. The hegumen Symeon, who became his spiritual father, tonsured him a monk under the name of Mark^[15]. Life on Antigone was however made precarious by the constant threat of Ottoman raids, which made it difficult to maintain a stable monastic life in that frontier zone^[16].

Mark and his spiritual father then withdrew to the Monastery of Saint George of the Mangana, in Constantinople itself, where the hegumen Symeon died and where Mark himself would end his life a quarter of a century later^[17]. It was in this monastery that Mark devoted himself to the in-depth study of the Church Fathers, composed liturgical offices (canons and hymns in honour of Christ, of the Mother of God and of the angels) and wrote several treatises defending the theology of Saint Gregory Palamas^[18], who died in 1359 and was then at the heart of intense Byzantine controversies on the distinction between the divine essence and energies — the so-called Palamite question, on which Mark resolutely sided with the hesychast doctor, whose memory he venerated all his life^[19].

Episcopal consecration and the Byzantine context

Around 1437, on the eve of the departure for the council of union, Emperor John VIII Palaiologos (1392-1448) persuaded Mark, despite his reluctance, to accept the office of Metropolitan of Ephesus^[20]. The choice was not insignificant: the ancient apostolic see of Ephesus — linked to Saint John the Evangelist and to the Third Ecumenical Council of 431 which proclaimed Mary Theotokos there — was then largely occupied by the Turks and emptied of its Christian population, so that Mark's metropolitan dignity was in practice titular^[21]. He sat at the council as representative of the Patriarchate of Alexandria, whose holder could not make the journey^[22].

The political context driving Byzantium toward Rome was dramatic: reduced to Constantinople and a few scattered territories, the Byzantine Empire had no hope left of repelling the Ottoman advance other than a Western crusade, which presupposed prior religious reunification with Rome^[23]. It was this military and political urgency, more than theological conviction alone, that explains the presence of the emperor in person at the head of a delegation of nearly seven hundred Byzantines^[24].

A defender of Saint Gregory Palamas

Even before the council, Mark had already established himself as one of the most rigorous continuators of hesychast theology and of the essence-energies distinction defended by Gregory Palamas — the thesis that God, inaccessible in His essence, truly communicates Himself to men through His uncreated energies, notably in the light of Tabor contemplated by the hesychast monks^[25]. This Palamite formation deeply colours his Trinitarian theology: for Mark, any idea of a procession of the Spirit from the Son, even understood as simple mediation, threatens in his view the order of Trinitarian relations established by the Cappadocian Fathers and reopens, in his eyes, the door to a confusion between the Person of the Father — sole source (monè aitia) in the Trinity — and the other Persons^[26].

Orthodox tradition sums up the spirit of his conciliar writings by lending him this principle: in matters of faith, no accommodation is permitted^[27].

It was in this spirit that Mark approached the council: not as a diplomatic negotiation in which one compromises on secondary points, but as the defence of a deposit received intact from the Fathers, which no political reason, even the survival of the Empire, could legitimately diminish.

The journey and the opening of the council

The Byzantine delegation, led by Emperor John VIII Palaiologos and Ecumenical Patriarch Joseph II, left Constantinople on 27 November 1437 and reached Venice in February 1438^[28]. The council — technically the continuation of the Council of Basel, transferred by Pope Eugene IV (Gabriele Condulmer, pope from 1431 to 1447), who sought to remove the assembly from the conciliarist movement — opened at Ferrara in spring 1438, then moved to Florence in January 1439 for financial and sanitary reasons (threat of plague)^[29]. Some seven hundred Greeks — bishops, monks, clerics, imperial officers, including twenty-two metropolitans — took part alongside the Latin delegation, itself led by Cardinal Giuliano Cesarini^[30].

At Florence, the Catholic Church counts this council as the Seventeenth Ecumenical Council (in the Basel-Ferrara-Florence-Rome series, 1431-1449)^[31]. For the East, it would only be received — and rejected — as an abortive attempt.

The discussion on the Filioque: Mark facing the Latin theologians

The Filioque occupies nine consecutive sessions, from October 1438 to March 1439, and constitutes the principal theological knot of the council^[45]. The Dominican John of Ragusa, then above all Cardinal Juan de Torquemada, expound the Latin doctrine: the Father and the Son are not two distinct principles of the Holy Spirit, but a single principle, the Son holding from the Father Himself His capacity to make the Spirit proceed — so that to say the Spirit proceeds from the Father and the Son is to say He proceeds from the Father through the Son^[46].

Mark refuses this solution, including in the softened form of the Eastern formula "through the Son" (dia tou Huiou), which other Greek delegates, notably Bessarion, judged acceptable as a legitimate Eastern equivalent of the Latin Filioque^[47]. For Mark, this equivalence is itself an equivocation: to accept that the Son intervenes in one way or another in the eternal procession of the Spirit is, in his view, to introduce a second principle into the Trinity, in contradiction with the teaching of the Cappadocian Fathers on the Father as the unique source without source (monè aitia, anarchos aitia)^[48]. He further opposes the classic canonical argument: the Third and Fourth Ecumenical Councils (Ephesus 431, Chalcedon 451) are said to have forbidden any addition to the Nicene-Constantinopolitan Symbol, which would make the Latin insertion of the Filioque — introduced in Spain in the 6th century and then generalized in the West — canonically illegitimate, regardless even of its doctrinal truth^[49].

The discussion on purgatory

Once the Filioque has been discussed, the council turns to the question of purgatory. The principal Latin speakers are Cardinal Cesarini and above all Juan de Torquemada, whose discussion with Mark is described by witnesses as particularly lively^[50]. Mark writes on this occasion his most substantial treatise, the Latin Refutations on the Fire of Purgatory^[51].

It is essential to specify — against a too widespread caricature — what Mark grants and what he refuses. He grants the essentials of the common practice and doctrine: prayer for the dead is universal in the Byzantine liturgy; there exists for certain souls a post-mortem purification; the suffrages of the living can help the dead. What he refuses is the idea of a material fire of punishment before the Last Judgment, which he judges foreign to the Greek patristic tradition^[52].

In substance, his thesis is that the idea of a punishment suffered before the Last Judgment, in the form of a material purifying fire, is foreign to the tradition of the Church^[53].

He nevertheless admits that certain souls experience after death a transitory state from which the prayers of the Church can free them^[54]. A position which, as will be seen, brings his doctrine much closer to Catholic teaching than is often said.

The question of Roman primacy

The third point — the primacy of the Roman pontiff — is settled last, almost in haste, as the health of the old Patriarch Joseph II declines (he dies at Florence on 10 June 1439, not without having himself signed a personal declaration accepting Filioque, purgatory and Roman primacy)^[55]. The final bull defines:

"We define that the holy apostolic see and the Roman pontiff hold the primacy over the whole world; and that this same Roman pontiff is the successor of blessed Peter, prince of the apostles, and the true vicar of Christ, the head of the whole Church, the father and teacher of all Christians; and that to him, in the person of blessed Peter, was delivered by our Lord Jesus Christ the full power of feeding, ruling, and governing the universal Church."^[56]

This is the first explicit conciliar definition of pontifical primacy of jurisdiction, four centuries before Pastor Aeternus (Vatican I, 1870)^[57]. Mark, already broken with the council over the Filioque and purgatory, sees in it the confirmation that the proposed union amounts to pure and simple submission of the East to Rome, and not to a reconciliation between equals^[58].

The three points debated at the council can be summarized as follows:

Bessarion and Mark: two opposite trajectories

The most striking contrast of the council sets Mark against Bessarion (Basil Bessarion, 1403-1472), Greek metropolitan of Nicaea, who delivers in April 1439 a decisive speech in favour of the union and himself reads the Latin bull, in Greek, from the pulpit of the cathedral of Santa Maria del Fiore, alongside Cardinal Cesarini^[63]. Bessarion will be made a cardinal by Eugene IV, will settle in Rome, will become one of the great humanists of the Italian Renaissance there, and will die a Catholic in 1472. Mark, for his part, returns to Constantinople to lead there, until his death, the opposite combat. Two opposite itineraries, born of the same council, of the same Byzantine culture and often of the same masters — a sign that the divide did not reflect an opposition between "pure Greeks" and "agents of Rome", but a real theological disagreement, painfully lived within the Byzantine intellectual elite itself^[64].

The saying attributed to Eugene IV

On 6 July 1439, in the cathedral of Florence, the bull Laetentur Caeli is solemnly proclaimed, read alternately in Latin by Cardinal Cesarini and in Greek by Bessarion^[65]. All the Greek prelates present have affixed their signature, with a single exception: Mark of Ephesus. According to an anecdote that has remained famous in the historiography of the council, reported notably in the wake of the eyewitness Sylvester Syropoulos, Pope Eugene IV, learning of the absence of the Bishop of Ephesus's signature, is said to have reacted, according to the historiographical tradition, by observing that without the Bishop of Ephesus he had accomplished nothing^[66].

This saying, transmitted by the historiographical tradition of the council in the wake of the eyewitness Syropoulos, reflects a definite political reality: the legitimacy of the union in the East rested on the displayed unanimity of the Greek episcopal body, and the absence of a single signature — that of the most respected theologian of the delegation — was enough to compromise its reception^[67].

What Mark really held against the union

It would be reductive to present Mark's refusal as simple personal stubbornness. Three distinct grievances combine in it, which recent historiography has made it possible to rank more precisely^[68]:

1. A real doctrinal disagreement on the Filioque, which he considered — wrongly according to Catholic teaching, but sincerely — as a substantial alteration of the Trinitarian faith of the Fathers, and not as a simple nuance of vocabulary.
2. An ecclesiological disagreement on the nature of Roman primacy, which he judged incompatible with the conciliar and synodal model he held to be normative in the undivided Church of the first seven ecumenical councils.
3. A deep distrust of the very method of the council: Mark considered that the Greek delegation, a minority, linguistically isolated and financially dependent on pontifical generosity, was not in a position to negotiate freely — a judgment shared by part of modern historiography on the real balance of power at Ferrara-Florence^[69].

Mark returns to the East on the same ship as the emperor, without having yielded^[70].

Return to Constantinople and flight to Mount Athos

Back in Constantinople in February 1440, the delegation finds a population and a lower clergy largely hostile to the union^[71]. The unionist Patriarch Metrophanes II, installed after the death of Joseph II, seeks to silence the open opposition Mark is leading from his monastery. In May 1440, under threat, Mark flees to Mount Athos, the monastic republic where he hopes to find support for his resistance^[72].

Imprisonment on Lemnos (1440-1442)

Overtaken by the unionist authorities, Mark is arrested and forcibly held for nearly two years, from 1440 to 1442, in a monastery on the island of Lemnos, in the Aegean Sea^[73]. This detention, motivated exclusively by his refusal to rally to the union, makes him in the eyes of his partisans a confessor persecuted for the faith — a status that directly prepares his future canonization as a moral martyr of Orthodoxy^[74].

The encyclical letter of summer 1440

It is during this period of resistance, before his arrest, that Mark writes his Encyclical Letter (summer 1440), addressed "to all Orthodox Christians on earth", in which he explicitly calls for the rejection of the union and bluntly describes the Latin position as heretical:

"The Latins are not only schismatics, but heretics; and we have separated from them for no other reason than that they are heretics."^[75]

This formula, of a harshness that cannot be softened, shows that Mark did not conceive the rupture as a simple disciplinary or jurisdictional divergence, but as a doctrinal necessity of conscience. It is this tone — and not only its technical content — that explains why his influence weighed so heavily on the definitive failure of the union in the East: a specialists' disagreement on the procession of the Holy Spirit could, with time, have been absorbed by the Churches; the accusation of heresy, levelled by the most respected theologian of the anti-unionist camp, closes on the contrary every path to peaceful reception.

The last months and the spiritual testament

Freed around 1442, Mark returns to Constantinople and to the Monastery of Saint George of the Mangana, where he pursues, despite declining health, his combat against the union by word and by writing, gradually entrusting the succession to his disciple George Scholarios (the future Patriarch Gennadius II)^[76]. On his deathbed, in June 1444, he is reported to have declared, in a discourse recorded by his disciple:

"I wish to express my thought openly and more clearly: I prefer to separate myself from those who think otherwise, rather than unite with them in concord, abandoning the pious faith taught to me by the Fathers."^[77]

According to the same tradition, transmitted by Scholarios, Mark is said to have charged him on his deathbed to continue, alone henceforth, the defence of Orthodoxy against Latin influence — a mandate Scholarios would honour by becoming, after the fall of Constantinople, the first ecumenical patriarch under Ottoman domination and one of the most determined artisans of the definitive repudiation of the union^[78].

Death, 23 June 1444

Mark dies on 23 June 1444, at the age of fifty-two, at the end of a two-week intestinal illness, at the Monastery of Saint George of the Mangana where he had spent most of his monastic life^[79]. Certain ancient sources — still repeated by a few reference works — place his death in 1445; the most recent chronological reconstruction, based on a critical re-examination of the primary sources, confirms however 1444 as the most solidly established date^[80].

Gennadius Scholarios and the definitive failure of the union

After Mark's death, George Scholarios takes up the torch of opposition to the union, with an intellectual authority almost equal to that of his master^[81]. Having become a monk under the name of Gennadius, he is enthroned, after the fall of Constantinople, as the first ecumenical patriarch recognized by Sultan Mehmed II in 1454. Under his patriarchate, the Union of Florence is officially and definitively repudiated by the Church of Constantinople^[82].

The fall of Constantinople (1453) and the myth of punishment

On 29 May 1453, Constantinople falls to the Ottoman troops of Mehmed II, ending eleven centuries of Byzantine Empire. The Western military aid the union was supposed to trigger never comes on the hoped-for scale^[83]. Part of the Greek people interpreted this catastrophe as a divine punishment for the "perjury" of Florence — a providentialist reading that is historically questionable (the military, political and technological causes of the fall of the city are well documented and independent of the council), but which still weighs today on Orthodox collective memory and finished disqualifying, in Greek eyes, even the memory of the union^[84].

The Orthodox canonization of 1734

It is only nearly three centuries later, in 1734, that Patriarch Seraphim I of Constantinople officially proclaims the canonization of Mark of Ephesus, celebrated since as a confessor who suffered persecution for the integral defence of the faith^[85]. His feast is fixed on 19 January, the day of the translation of his relics to the Monastery of Saint Lazarus in Galata. The Orthodox Church associates him, in her liturgical memory, with Photius of Constantinople and Gregory Palamas, as one of the three great "pillars of Orthodoxy" facing Rome^[86].

This canonization naturally binds only the Orthodox Church: the Catholic Church does not recognize Mark of Ephesus as a saint, precisely because she continues to hold as true the doctrines he fought in the name of faith. Certain French-language resources, including some popular devotional calendars, sometimes mention his name ambiguously; it matters to state unequivocally that no Catholic recognition of sanctity concerns him^[87].

The Filioque: neither two principles, nor a mere word

Mark's central objection — that the Filioque would introduce a second principle into the Trinity — rests on a reading of the Latin term processio which Catholic theology does not recognize as its own. The Catechism of the Catholic Church teaches that the Father is the first and unique source, but that the Son receives from the Father, from all eternity, to spirate the Spirit with Him^[88]. In 1995, the Pontifical Council for Promoting Christian Unity specified this distinction in terms which recognize the legitimacy of the Greek formulation itself: the Greek term ekporeusis, used by the Cappadocian Fathers, strictly designates the hypostatic origin of the Spirit from the Father alone as principle without principle, while the Latin term processio is broader and designates the communication of the consubstantial divinity "from the Father, through and with the Son, to the Holy Spirit"^[89]. The two traditions, thus specified, are therefore not contradictories, but complementary expressions of one and the same Trinitarian mystery, as recognized by the joint declaration of the North American Orthodox-Catholic Theological Consultation of 2003:

"The theologians of both [Catholic and Orthodox] traditions recognize that the Western and Eastern positions on the eternal procession of the Holy Spirit, as taught in their classic form by the Fathers of each tradition, should now be recognized as complementary rather than contradictory."^[90]

Mark's categorical refusal, including of the intermediate formula "through the Son", thus appears, in the light of this belated clarification, more rigid than his own Greek patristic tradition required, a far from negligible part of the Greek Fathers themselves having used formulas close to procession through the Son without seeing in them any attack on the monarchy of the Father^[91]. For the complete treatment of this question — Greek and Latin patristic sources, history of the liturgical insertion, detailed answer to each objection — see the article Answers to Orthodox Objections.

Purgatory: a narrower disagreement than it appears

On purgatory, an attentive reading of Mark's own writings reveals a largely underestimated agreement of substance. The Catholic Church teaches, with the Catechism, that:

"All who die in God's grace and friendship, but still imperfectly purified, are indeed assured of their eternal salvation; but after death they undergo purification, so as to achieve the holiness necessary to enter the joy of heaven."^[92]

The Catechism itself specifies that the image of the "cleansing fire" is a traditional way of designating this purification, without the Church imposing a physical conception of fire as a material element identical to the fire of this world^[93]. Yet that is precisely what Mark refused: not post-mortem purification itself — which he explicitly grants — but too material a representation of the purgative fire, such as could circulate in a little-nuanced 15th-century Latin popular piety. On the three essential points — reality of the purification, efficacy of the prayer of the living, possibility for the dead to emerge purified — Mark and Catholic teaching largely converge^[94]. The final disagreement, at Florence, therefore bore less on doctrinal substance than on an image and a word — as confirmed by the very final text of the bull, which precisely renounces imposing either the Latin term purgatorium or the idea of a material fire, retaining only the formula of "purifying pains"^[95]. For the complete doctrinal treatment of purgatory — scriptural, patristic and conciliar foundation — see the article Purgatory.

Roman primacy: what Florence defined

On primacy, by contrast, the disagreement remains whole and structural: what Laetentur Caeli defines as primacy of universal jurisdiction, founded on the Petrine mission (Mt 16:18-19), Mark — like Orthodox theology in general — receives at most as a primacy of honour within a synodal system in which no bishop, even the Bishop of Rome, holds a power of direct government over the other Churches^[96]. This point remains today still, six centuries after Florence, the principal knot of Catholic-Orthodox theological dialogue^[97]. The Second Vatican Council, in the decree Unitatis Redintegratio, chose a different path from Florence's: rather than first demanding the integral doctrinal acceptance of primacy as formulated in 1439, it invites first recognizing the legitimacy of the diversity of theological, liturgical and disciplinary traditions inherited from the Eastern Churches:

"Far from being an obstacle to the unity of the Church, diversity of customs and observances only adds to her beauty."^[98]

The same decree explicitly recognizes that Eastern theological traditions are "rooted in an excellent way in the Holy Scriptures" and lead "to a righteous way of life, and even to full contemplation"^[99] — a recognition which would doubtless have disarmed part of Mark's suspicions toward a West he perceived as standardizing.

A sincere opponent rather than a heretic in bad faith

The Catholic Church has no reason to present Mark of Ephesus as a man of bad faith or a mere political obstructionist. His theological competence, his intellectual consistency and the considerable personal price he paid — exile, imprisonment, death far from any official recognition in his lifetime — attest to an upright conscience, even when it errs on real points of doctrine. It is precisely this honesty that makes his case theologically interesting: it shows that a disagreement can be born not of malice, but of a real divergence on the exact nature of Trinitarian relations, on ecclesiology and on the legitimate place of diversity in the unity of the Church — a divergence the Catholic Church continues to judge real on the Filioque and primacy, but which she today recognizes as narrower than it appeared in 1439 on purgatory, and on which she has made, since Vatican II, a sincere effort of clarification and listening^[100].

Part of 20th-century Western historiography, including among Catholic authors sympathetic to the union, has sometimes presented Mark as a rigid mind, less philosophically refined than Bessarion or certain Latin theologians, and whose intransigence owed more to temperament than to competence^[101]. The classic work of Joseph Gill, The Council of Florence (1959), which remains the unavoidable scholarly reference on the proceedings of the council, thus tends to present the conciliar process from the viewpoint of its diplomatic success, which sometimes leaves Mark in the role of the difficult opponent rather than that of the full-fledged theological interlocutor^[102].

Part of contemporary scholarship proposes a markedly different reassessment. The most recent study, published in 2025 in the Journal for Late Antique Religion and Culture, revisits all the available sources to argue that Mark was in reality a conciliar theologian of remarkable competence and attentiveness, endowed with a patristic knowledge superior to that of several of his Latin counterparts, and that his role as the "conscience" of the Byzantine delegation — the expression is the historian Steven Runciman's — deserves to be taken seriously on the strictly intellectual plane, and not only on that of moral resistance^[103].

This reassessment changes nothing, from the Catholic point of view, in the judgment on the content of Mark's theses on the Filioque and primacy: they remain, for the Catholic Church, theologically insufficient positions, and not truths unrecognized by the West. But it invites never confusing, in judging a theological opponent, the soundness of convictions with the validity of arguments: one can — and one must, in a Catholic encyclopedia faithful to the demand for truth — fully recognize the former without conceding the latter. It is this double demand, rather than the comfort of a caricature in one sense or the other, that makes it possible to understand why a single man could, by his missing signature alone, change the course of a history of several centuries.

• Answers to Orthodox Objections — complete doctrinal treatment of the Filioque, of Roman primacy, of the schism of 1054 and of the lifting of the anathemas of 1965.
• Purgatory — scriptural, patristic and conciliar foundation of the Catholic doctrine of purgatory.
• Indulgences — the Catholic practice linked to the purification of the souls in purgatory.
• Gregory Palamas — the hesychast theologian whose continuator Mark of Ephesus claimed to be.
• Photius I of Constantinople — the other great "pillar of Orthodoxy" venerated alongside Mark.
• Michael Cerularius — the patriarch of the schism of 1054, more than three centuries before Mark of Ephesus.
• The Great Schism of the East — the historical context of the rupture of 1054, from which the Council of Florence attempted, without lasting success, to emerge.
• Pope Eugene IV (1431-1447) — the pope who convoked and presided over the Council of Ferrara-Florence.
• The Fall of Constantinople (29 May 1453) — the collapse of the Byzantine Empire, nine years after the death of Mark of Ephesus.
• Nestorius — another biographical portrait of a Byzantine theologian in rupture with Rome, on a distinct Christological dispute.
• The Dogma of the Immaculate Conception and The Assumption of the Virgin Mary — two Marian dogmas not received by Orthodoxy, mentioned in the broader context of Catholic-Orthodox dialogue.