The Same Fire

For seven centuries the names of Thomas Aquinas and Gregory Palamas have functioned in popular polemics as twin banners of irreconcilable confessional armies. To be Catholic, on this telling, is to confess God as actus purus essendi — the simple act of being whose essence is identical with His existence; to be Orthodox is to confess God as essence and energies, an unknowable ousia communicating itself through really distinct uncreated energeiai. The Latin tradition climaxes in the visio essentiae Dei; the Byzantine tradition in the vision of the uncreated Taboric light — and never the twain shall meet.

This framing almost guarantees a dead end. It presupposes that both men were trying to answer the same philosophical question with the same conceptual vocabulary and produced incompatible answers. That presupposition is now in serious historical doubt. A more productive question is this: when Aquinas describes God as the unparticipated esse in which the saints participate by lumen gloriae, and when Palamas describes God as essence inaccessible and energies participable, are they describing the same theotic reality in two different philosophical grammars?

If they are, then the apparent contradiction is largely a translation problem rather than a doctrinal one — and the Eastern Catholic Churches, which venerate Palamas as a saint while remaining in communion with the See of Peter, are not theological oxymorons but the lived institutional answer to a question Latin and Byzantine theologians spent centuries asking past each other.

I. A Discovery in the Translator’s Study

The decisive philological datum was identified by Fr Christiaan Kappes, a Byzantine Catholic priest who serves as Academic Dean and Professor of Liturgical and Dogmatic Theology at the Byzantine Catholic Seminary of SS. Cyril and Methodius in Pittsburgh, working in conversation with John A. Demetracopoulos of the University of Patras.

In the 1350s, the Byzantine humanist and statesman Demetrios Kydones undertook what was then an extraordinary intellectual project: translating the Summa theologiae of Thomas Aquinas into Greek. Kydones was no mere copyist. He was the most accomplished Byzantine Greek of his generation, a first-rate theologian who had already translated the Summa contra Gentiles (completed December 1355) and whose work brought Aquinas directly into the Greek-speaking intellectual world for the first time. What Kydones encountered in translating Aquinas forced him to make choices that, on reflection, are startling.

Aquinas’s technical Latin phrase actus essendi — the “act of being,” the most fundamental and perfective principle Thomas attributes to God and by which He gives being to all that is — had no obvious Greek equivalent. Kydones rendered it ἡ τοῦ εἶναι ἐνέργεια — hē tou einai energeia, “the energy of being.” The word he reached for was energeia: the very word at the centre of the Palamite controversy that had been raging in Constantinople for a generation.

This was not a blunder. Kydones was too careful for that. It was recognition. When the subtlest Latin theology of the fourteenth century was rendered by the most learned Byzantine Greek of the era, the word that came naturally to describe God’s most communicative, perfective, and participated principle was the same word Palamas had been using for God’s uncreated self-communication to creatures.

Kappes has developed this thesis across a substantial body of work, including his doctoral dissertation at the Aristotle University of Thessaloniki (2015) on the theology of George-Gennadios Scholarios, his monograph The Immaculate Conception: Why Thomas Aquinas Denied, while John Duns Scotus, Gregory Palamas, and Mark Eugenicus Professed the Absolute Immaculate Existence of Mary (Academy of the Immaculate, 2014), and his The Epiclesis Debate at the Council of Florence (Notre Dame, 2019). The philological finding about Kydones is documented most accessibly in Demetracopoulos’s foundational essay “Palamas Transformed: Palamite Interpretations of the Distinction between God’s ‘Essence’ and ‘Energies’ in Late Byzantium” (in Greeks, Latins, and Intellectual History 1204–1500, Peeters, 2011).

The implication reaches further than philology. Palamas himself — contrary to the standard narrative — was working in a world already shaped by translated Latin scholasticism. His mature writings show engagement with thirteenth-century Latin theological methodology, and his most important theological heirs would explicitly use Latin scholastic categories to defend his teaching. The supposed civilizational gulf between Latin rationalism and Greek mysticism was not a fourteenth-century reality. It was, as Norman Russell’s magisterial Gregory Palamas and the Making of Palamism in the Modern Age (Oxford University Press, 2019) demonstrates, largely a twentieth-century construction — the joint product of Martin Jugie’s hostile Thomism and the polemical neo-Palamism of Lossky and early Meyendorff.

II. Aquinas on Deification: Solus Deus Deificat

The objection that Aquinas has no doctrine of deification — that the Latin tradition lost the patristic vocabulary of theosis somewhere between Augustine and the high Middle Ages — was the operating premise of much twentieth-century neo-Palamism. It does not survive contact with Aquinas’s actual text.

The watershed scholarly correction was Anna Williams’s The Ground of Union: Deification in Aquinas and Palamas (Oxford University Press, 1999), which argued in meticulous detail that deification is not a marginal motif in Aquinas but a structural centre that organises his soteriology and is architecturally parallel to the Palamite account. Williams’s specific theses have been refined and in places contested by subsequent scholarship — Richard Cross raised important questions in Journal of Theological Studies 69 (2018), and Luke Martin in New Blackfriars 98 (2017) — but her core finding, that Aquinas has a robust doctrine of deification structurally analogous to Palamas’s, has become a settled point of contemporary scholarship. Marcus Plested’s Orthodox Readings of Aquinas (Oxford University Press, 2012) reinforces the picture from the other direction, tracing Aquinas’s enthusiastic reception in the Byzantine world and concluding that the picture of Aquinas as a mysticism-hostile Latin rationalist is not one his fourteenth-century Greek readers would have recognised.

The principal Thomistic loci are well known once one knows to look for them. ST I-II, q. 110, a. 1 defines grace as “participatio divinae naturae,” citing 2 Peter 1:4 directly — the same verse that is the scriptural foundation of the Greek theotic tradition. ST I, q. 43 teaches that in sanctifying grace the Trinity does not merely produce created effects but gives Itself: “the divine person Himself is given,” dwelling in the soul “as the known in the knower and the beloved in the lover.” This is uncreated communion — not a moral deposit, not a created quality substituting for God, but the living God present at the creature’s deepest ground. ST III, q. 1, a. 2 gives the Christological architecture: ut hominem faceret deum, that He might make man God. Aquinas is citing Athanasius directly and repeating the patristic admirabile commercium that both Latin and Byzantine theology share as common inheritance.

Solus Deus deificat. Only God deifies. As it is impossible that anything save fire should enkindle, so it is impossible that anything save God should deify. St Thomas Aquinas · Summa Theologiae I-II, q. 112, a. 1

The structuring matrix is Aquinas’s celebrated exitus-reditus schema — all things proceed from God as their first cause and return to Him as their final end — which is theotic to the core. The reditus of the rational creature just is deification: accomplished through Christ, administered through the sacraments, grounded in the indwelling Trinity, and completed in the lumen gloriae. Aquinas’s constant use of Pseudo-Dionysius — the Divine Names, the Celestial Hierarchy, the Mystical Theology — means that the apophatic tradition central to Eastern hesychasm is also central to the Latin Doctor Communis. In the Catena Aurea and the Sentences commentary, Aquinas quotes Dionysius’s classic definition of deification — theōsis estin hē pros theon hōs ephikton aphomoiōsis te kai henōsis, “deification is assimilation to and union with God as far as is possible” — as a technical definition. He is breathing the same air.

The secondary scholarship now consolidates this decisively. Jared Ortiz’s edited volume Deification in the Latin Patristic Tradition (CUA Press, 2019) demonstrates that the deification motif runs from Tertullian to the high medieval West without interruption, killing the narrative of a Latin lacuna. David Meconi’s The One Christ: St. Augustine’s Theology of Deification (CUA Press, 2013) establishes the Augustinian foundation. Daniel Keating’s Deification and Grace (Sapientia Press, 2007) provides a lucid Catholic synthesis. Any contemporary discussion of Aquinas on grace that does not foreground theosis is simply behind the scholarly literature.

III. The Eastern Catholic Witness

If Aquinas and Palamas are saying recognizably the same thing in different grammars, this is not merely an academic claim. There exists, and has existed for centuries, a community of Christians who venerate both — in full communion with the Bishop of Rome and with a liturgical and dogmatic tradition rooted in Byzantium. The Eastern Catholic Churches are the lived institutional answer to the question. Before one can claim that accepting Palamas is incompatible with Roman communion, one must account for the fact that millions of Catholics have been doing both for three hundred years without Roman objection.

The Melkite witness is the sharpest. The Melkite Greek Catholic Church has long been the most theologically and liturgically Byzantine of the Eastern Catholic Churches. In 1971, the Holy Synod of the Melkite Church at Ain Traz formally restored the commemoration and Office of St Gregory Palamas on the Second Sunday of Lent to the Triodion — reversing earlier latinizing reforms. This was not done unilaterally. The decision was submitted to the Sacred Congregation for the Doctrine of the Faith; no objection was raised. Patriarch Maximos V Hakim communicated the Synod’s decision to Cardinal Franjo Šeper, Prefect of the CDF, in a letter of 29 August 1971. The Melkite Triodion, in full communion with Rome, today contains the full Office of St Gregory Palamas, including the troparion that hails him as “the lamp of Orthodoxy, the support and teacher of the Church.”

The theological corroboration comes from Mgr Gérard Philips (1899–1972), the Belgian dogmatician and principal redactor of Lumen Gentium — one of the most authoritative Catholic theologians of the Vatican II era. Philips judged the Palamite distinction to be “a typical example of a perfectly admissible theological pluralism” within the Catholic magisterium. The German theologian Jürgen Kuhlmann subsequently made the negative point with equivalent precision: “the denial of a real distinction between essence and energies is not an article of Catholic faith.” Taken together, these judgements define the Catholic position: Rome requires neither acceptance nor rejection of the Palamite distinction. It is an open theological question.

The Ukrainian Greek Catholic tradition has lived this question from within. Figures such as Cardinal Lubomyr Husar and the scholars associated with the Ukrainian Catholic University in Lviv have explicitly integrated Palamite hesychast spirituality with Catholic dogmatics. The Kyivan theological tradition cultivates the Philokalic inheritance without embarrassment. At the Byzantine Catholic Seminary in Pittsburgh, Fr Kappes’s own institution, the question is not “can we hold Palamas in communion with Rome?” but “how precisely do Palamas and Aquinas converge?” — a question the seminary addresses in its academic programme as a matter of course.

John Paul II gave this the highest magisterial framing. Orientale Lumen (2 May 1995) does not name Palamas but takes for granted the catholicity of Eastern theological idioms, urging Latin Catholics to “avail themselves more often of the spiritual riches of the Eastern fathers, which lift up the whole man to the contemplation of the divine mysteries.” His image of the Church breathing “with both lungs” is not a slogan but a dogmatic claim: the two traditions are not competing pneumatologies but two aspects of a single respiration. In his General Audience of 12 November 1997, JPII listed Palamas alongside Nicholas Cabasilas and Gennadios Scholarios as “great theological writers” of the Christian East — in a specifically Marian context, noting that these distinctively Byzantine theologians prefigured the dogmatic definitions Rome would later make. The irony is pungent: the icons of Eastern resistance to Rome are here invoked as witnesses for the Catholic faith.

IV. The Formal Distinction: Where Two Grammars Can Meet

Where do the grammars actually diverge? Honestly: at the metaphysics of distinction. The entire question of whether Palamas and Aquinas can be reconciled turns on what kind of distinction one places between God’s essence and His self-communication to creatures.

The classical scholastic taxonomy offers a spectrum:

Thomists have insisted that anything less than identity in God violates divine simplicity. Palamites have insisted that some real, extra-mental, non-separable distinction is required to make sense of genuine participation in God. The Scotist formal distinction is the obvious mediating concept: it is a parte rei (the realism Palamites require) but not separative (the simplicity Thomists require). And this is not a modern proposal — it is the path taken by Palamas’s own most authoritative heirs.

John VI Kantakouzenos (emperor and theologian, d. 1383), Mark of Ephesus (d. 1444), and above all George Gennadios Scholarios (d. ca. 1472) all read the Palamite distinction as kat’ epinoian — a conceptual distinction with foundation in the thing, functionally equivalent to Scotus’s formal distinction. This is the central argument of Demetracopoulos’s “Palamas Transformed,” which documents in painstaking detail how the most learned Palamites of the late Byzantine period “softened the harsh Palamite distinction” and adopted an analysis compatible with Latin scholastic categories. Scholarios went further: in his 1445 Defense of Gregory Palamas against Aquinas’s De ente et essentia, he argued explicitly that had Aquinas known the Scotist formal distinction, he would have placed essence and energies there — and the controversy would never have arisen.

Had Thomas Aquinas known the formal distinction of Scotus, he would have placed essence and energies precisely there — and the Palamite controversy would never have needed to arise. George Gennadios Scholarios · Defense of Gregory Palamas against Aquinas’s De ente et essentia · 1445

The implication is striking: the saints to whom contemporary Orthodoxy most appeals — Mark of Ephesus, the champion of Eastern theology at Florence; Scholarios, the first Patriarch of Constantinople under Ottoman rule — did not read Palamas as requiring a strong real distinction in God. They read him as compatible with the Scotist formal distinction and engaged Aquinas seriously on those terms. The neo-Palamite claim that Palamas requires a distinctio realis in the strong compositional sense is, on the historical evidence, not the claim of Palamas’s most learned heirs. It is a twentieth-century theological move.

Norman Russell’s 2019 study makes this case at book length. His conclusion deserves direct quotation: the “Palamism” constructed in opposition to Western theology is “largely a twentieth-century invention by Martin Jugie (hostile) and John Meyendorff (apologetic),” and when freed from this construction, Palamas’s theology is capable of “fruitful use by contemporary Western and Eastern theologians without the need to subscribe to what has been regarded as ‘Palamism’.” This is not ecumenical wishful thinking from a Catholic. Russell is a careful, sober historian of Byzantine theology whose reading of the primary sources supports the revisionist conclusion.

V. Two Grammars, One Fire

What would genuine convergence actually look like? It would look like six honest recognitions, none of which requires either tradition to surrender its genuine insights.

First: both traditions confess the same theotic reality. God is utterly transcendent and unknowable in His essence. He is also genuinely, ontologically communicative — He gives Himself to the rational creature elevated to behold and participate in Him, through Christ, by the Spirit, in the Church and her sacraments. Aquinas calls the creature’s term visio beatifica by lumen gloriae: a participation in God’s own self-knowledge requiring elevation by the very God who is the object. Palamas calls it the vision of the uncreated light — a participation in the divine energeiai requiring illumination of the creature by the very God who shines forth. The architecture is the same.

Second: both traditions ground theosis in the Incarnation. Aquinas’s ut hominem faceret deum and Palamas’s insistence that “in Christ the divinity dwells bodily, and from His fullness we have all received” are different vocalizations of the same patristic admirabile commercium. Neither tradition has a doctrine of deification that floats free of Christology.

Third: both traditions require some metaphysical account of how the infinite God becomes genuinely accessible to the finite creature. Aquinas’s account runs through the divine missions, the participated lumen gloriae, and the analogous distinctions among the divine attributes. Palamas’s account runs through the essence/energies distinction. The Scotist formal distinction, embraced by Mark of Ephesus and Scholarios, provides a coherent grammar for both — a parte rei but not separative, realistic but not compositional.

Fourth: both traditions must hold together transcendence and genuine participation. Pseudo-Dionysius, shared by both, insists on both terms simultaneously. Neither Aquinas nor Palamas was willing to sacrifice the divine transcendence for the sake of a reassuring immanence, or to sacrifice genuine deification for the sake of a safely abstract God. This shared commitment is the deep structural ground of the convergence.

Fifth: the formal ecumenical dialogue has slowly recognized this. The Joint International Commission for Catholic-Orthodox Theological Dialogue has, since its 1982 Munich statement, progressively articulated a shared theology of communion in patristic categories. The 1993 Balamand Declaration recognized that the Eastern Catholic Churches “have the right to exist and to act in answer to the spiritual needs of their faithful” — granting implicit recognition that a Catholic theology in Palamite idiom is legitimately Catholic. Ut Unum Sint (1995), §54, calls explicitly for examination of how far “various theological formulations” of disputed doctrines express the same faith in different idioms — precisely the methodology the Williams-Plested-Russell-Kappes scholarship has applied, productively, to Palamism.

Sixth: the historical record refutes the ideological construction. Behind the twentieth-century narrative of Aquinas-versus-Palamas stands a fourteenth-century reality very different from its image. Kydones renders actus essendi as hē tou einai energeia. Palamas works with Latin scholastic sources via Kydones’s translations. Nicholas Cabasilas, the great Palamite saint, draws enthusiastically on Aquinas. Mark of Ephesus argues the Palamite case at Florence with the help of the Scotist formal distinction. Scholarios produces Greek translations of Aquinas’s Aristotle commentaries while defending Palamas. These are not the actions of men who thought they were building an insurmountable wall between East and West. They are the actions of men who thought they were working on the same problem with tools drawn from both sides of a sea — the same sea that, until the eleventh century, the Church had always crossed in both directions.

The Eastern Catholic Churches are, in this perspective, not the awkward exceptions that prove the rule of Eastern-Western incompatibility. They are the rule. They are the institutional continuation of the late Byzantine theological milieu in which Cydones and Cabasilas and Scholarios read Aquinas without embarrassment and in which the Palamite distinction was defended with Scotist tools. They are the communities who have stood between the two flames for three centuries and known, at the altar and in the icon screen and in the liturgical offices, that the two flames are one.

Aquinas died writing a commentary on the Song of Songs, having laid down his pen with the words: “Such things I have seen that all I have written seems like straw.” Palamas died at prayer, his last recorded words a farewell to “the light.” Both men, at the end, fell silent before the same mystery — the God who is fire and light and love, whose simplicity is not a negation but an infinite plenitude, who gives Himself wholly while remaining wholly Himself, and who deifies the creature not by abolishing its finitude but by filling it beyond all measure.

That is the same fire. It was always the same fire.