Perichoresis and the Enhypostaton

St. John of Damascus’s lasting contribution to Christology was terminological: he gathered the scattered conceptual vocabulary of the post-Chalcedonian centuries and fixed it with a precision that made his Exact Exposition the standard textbook of Orthodox dogma. This file treats four of those consolidated terms — perichoresis applied to the natures of Christ and to the Trinity, the enhypostaton (Leontius’ legacy refined), the composite hypostasis, and the formalized communicatio idiomatum — with the key chapters of Exposition Book III quoted per NPNF II/9.

Tradition: Pan-Orthodox (Church Father)

A Systematizer, Not an Innovator

John of Damascus (c. 675–749) wrote at the end of the great age of christological definition. Chalcedon (451) had confessed two natures in one hypostasis; Constantinople II (553) had read that confession in a firmly Cyrillian key; Constantinople III (680–681) had added the two natural wills. What remained was to gather this conciliar deposit into a single ordered exposition with a stable technical vocabulary — and this is precisely what John did in Book III of his Exact Exposition of the Orthodox Faith, the dogmatic third part of his Fount of Knowledge. He claimed no originality: “I shall say nothing of my own, but shall gather together into one the things worked out by the most eminent of teachers and make a compendium of them” (John of Damascus, Fount of Knowledge, prologue; trans. Chase, FOTC 37). Modern scholarship reads him exactly so — as the supremely accomplished organizer who “set the seal on the patristic achievement” and handed it to both Byzantine and Latin posterity (Louth, St John Damascene, Oxford 2002, ch. 6).

Perichoresis: From Gregory’s Verb to John’s System

The most consequential of the terms John consolidated is perichoresis (περιχώρησις, “mutual interpenetration,” “coinherence”). Its history is precisely traceable. The verb perichōreō is first deployed christologically by St. Gregory the Theologian (Nazianzen, d. 389/90), who used it of the reciprocal passing of names and properties between the divinity and humanity of the one Christ. St. Maximus the Confessor (d. 662) is the first to use the noun perichoresis, still in a christological register, for the mutual penetration of the natures (Scalise, “Perichoresis in Gregory Nazianzen and Maximus the Confessor”; the verb-to-noun development and Gregory–Maximus sequence are the settled findings of the scholarship, summarized at Louth, St John Damascene, ch. 6). John of Damascus is the figure who systematizes the term in two directions at once: he uses it for the coinherence of the two natures of Christ, and he extends it to the mutual indwelling of the three Persons of the Trinity, where it would become the technical term for Trinitarian coinherence in all later theology (Louth, St John Damascene, ch. 5–6).

Applied to Christ, perichoresis names the mutual permeation of the natures within the one hypostasis — but John guards it carefully against any Eutychian reading. The interpenetration is real, yet it is not symmetrical: it flows from the divine side. “The natures of the Lord permeate one another, yet we know that the permeation springs from the divine nature; for it is the divine nature that permeates and penetrates all things, as it wills, while nothing penetrates it” (John of Damascus, Exact Exposition III.7; trans. NPNF II/9). The flesh is deified by this permeation without being changed into divinity, just as iron in fire is permeated by heat without ceasing to be iron — John’s favored image for the union (John of Damascus, Exact Exposition III.17; trans. NPNF II/9; Louth, St John Damascene, ch. 6).

The asymmetry is the whole point. A symmetrical interpenetration — divinity passing into the flesh exactly as the flesh passes into divinity — would compromise the divine immutability and slide toward the Monophysite fusion John means to exclude. By insisting that the Godhead penetrates the manhood while remaining itself unpenetrated, John secures both the reality of the deification of Christ’s humanity and the unchangeableness of his divinity. Transferred to the Trinity, the same word does a different but analogous work: it names the mutual indwelling by which each Person is wholly in the others without confusion of the hypostases — “they are made one not so as to commingle, but so as to cleave to each other, and they have their being in each other … without any coalescence or commingling” (John of Damascus, Exact Exposition I.8; trans. NPNF II/9). It is a measure of John’s systematizing genius that a single term, inherited as a christological verb, could be made to carry both the unity-in-distinction of the natures and the unity-in-distinction of the Persons, and that later theology would receive it from him as a fixed instrument for both. The scholarship is careful to credit the development rather than the invention to him: Gregory supplied the verb and the christological intuition, Maximus the noun, and a thinker such as John of Scythopolis may have stood between; John of Damascus supplied the systematic consolidation in both registers (Louth, St John Damascene, ch. 6).

The Composite Hypostasis

The hinge of John’s Christology is the composite hypostasis (hypostasis synthetos). The Logos who is eternally simple became, in the Incarnation, a single compound person — not a compound nature (which would be Monophysitism), but one hypostasis in which two complete natures subsist. “The subsistence of God the Word … became compound, being compounded of the divinity which it always had and of the flesh which it assumed” (John of Damascus, Exact Exposition III.7; trans. NPNF II/9). The unity is at the level of person; the duality is at the level of nature. This formula lets John hold together Cyril’s insistence on a single subject and Chalcedon’s insistence on two natures: there is one who (the eternal Son) existing in two whats (Godhead and manhood), without confusion and without division (John of Damascus, Exact Exposition III.3–4; cf. Christology).

The Enhypostaton: Leontius Refined

How can Christ’s humanity be a complete human nature and yet not constitute a second human person? The Chalcedonian formula of “two natures in one hypostasis” had left a conceptual gap: if every nature normally exists as some concrete individual (a hypostasis), how can there be a real human nature in Christ that is not also a human person, without lapsing into Nestorianism? John’s answer is the doctrine of the enhypostaton (ἐνυπόστατον), the concept he inherits from the sixth-century Leontii (Leontius of Byzantium and Leontius of Jerusalem) and refines into a settled term. A nature, John clarifies, need not have its own hypostasis to be real; it may receive its concrete personal existence in another hypostasis. Christ’s human nature is neither anhypostatic (unreal, without any concrete existence) nor self-hypostatic (a person in its own right); it is enhypostatic — it subsists in the hypostasis of the Word. “The flesh of God the Word did not subsist as an independent subsistence … but rather, coming into existence in the subsistence of the Word, it became a subsistence which subsisted in another [enhypostatic], and did not become a subsistence which existed in itself” (John of Damascus, Exact Exposition III.9; trans. NPNF II/9, with the term rendered). The flesh, John adds, “is permitted neither to be without subsistence, nor to be a different subsistence” from the Word’s (Exact Exposition III.9; trans. NPNF II/9). This is the precise instrument that secures the integrity of Christ’s manhood — it is a full, rational-souled human nature — while denying it any independent personal center that would yield two sons. The human nature of Christ is fully real and fully complete; what it lacks is only its own hypostasis, because from the first instant of the Incarnation it came to be in the hypostasis of the Word, which thereby became the single personal subject of two natures. Scholars credit John with giving the term the lexical stability it had lacked in Leontius, fixing enhypostatos as the technical complement to the composite hypostasis (Louth, St John Damascene, ch. 6). This same instrument resolves the danger from the other side as well: because the flesh is enhypostatic in the Word and not anhypostatic, the human nature is no abstraction but the concrete, suffering, circumscribable humanity of the one Son — which is why the Word can be said to have truly hungered, wept, and died.

The Communicatio Idiomatum Formalized

There is a notable terminological convergence here that the scholarship observes: John can use perichoresis itself not only of the ontological coinherence of the natures but, following Gregory’s original christological usage, of the very reciprocity by which the properties and names of the two natures are exchanged in the one Christ. The communicatio idiomatum and the perichoresis of the natures are, in his usage, two descriptions of one reality — the one Person who is the single subject of both the divine and the human (Louth, St John Damascene, ch. 6).

From the single composite hypostasis follows the communicatio idiomatum (Greek antidosis idiomatōn, “exchange of properties”), which John formalizes into a rule of predication. Because one and the same person — the Word — is the subject of both natures, the properties of either nature may be truly predicated of the one Christ, even when named by a title proper to the other nature. “The Word appropriates to Himself the attributes of humanity … and He imparts to His own flesh His own attributes by way of communication, because of the interpenetration of the parts one with another, and because of the oneness … of His subsistence” (John of Damascus, Exact Exposition III.3; trans. NPNF II/9). So one may rightly say that “the Lord of Glory was crucified,” though the divine nature did not suffer, and that “God was born of the Virgin,” because the person born is the Word who is God (John of Damascus, Exact Exposition III.4; trans. NPNF II/9; cf. Christology, which sets out the same rule). John is careful with the grammar of the exchange: the properties are predicated of the person under either of his names, never of one nature as the other — “we do not say that the Godhead suffered in itself,” but that the Word suffered in the flesh (John of Damascus, Exact Exposition III.3–4; trans. NPNF II/9). This precise formalization is the dogmatic ground of the title Theotokos and the bridge between his Christology and his later defense of the icons: because the Word truly made a circumscribable human nature his own, that nature — and so the person depicted through it — can be portrayed (cf. Christology; John of Damascus, Three Treatises on the Divine Images).

Why the Vocabulary Mattered

The achievement of these chapters is not a new doctrine but a fixed doctrine. By stabilizing perichoresis, the composite hypostasis, the enhypostaton, and the antidosis as a coherent set of terms, John gave the Church a single grammar in which to confess the union: one composite person; two natures coinhering by an asymmetrical perichoresis flowing from the divine; a human nature real because enhypostatic; and an exchange of properties grounded in the identity of the subject. Every later Orthodox dogmatics, and much Latin Scholastic Christology through the De Fide Orthodoxa in Burgundio of Pisa’s twelfth-century translation, would reach for Christology through this vocabulary (Louth, St John Damascene, ch. 6; cf. The Two-Wills Inheritance for the parallel consolidation of will and operation).

References

John of Damascus. An Exact Exposition of the Orthodox Faith (Ekdosis akribēs tēs orthodoxou pisteōs), Book III, esp. chapters 3, 4, 7, 9, 17. c. 743. Trans. NPNF II/9 (ed. Schaff and Wace); also trans. Frederic H. Chase, Jr., Fathers of the Church 37 (Washington, DC: Catholic University of America Press, 1958).
John of Damascus. The Fount of Knowledge, prologue. Trans. Chase, FOTC 37.
John of Damascus. Three Treatises on the Divine Images. Trans. Andrew Louth, Popular Patristics Series 24. Crestwood, NY: St. Vladimir’s Seminary Press, 2003.
Louth, Andrew. St John Damascene: Tradition and Originality in Byzantine Theology. Oxford Early Christian Studies. Oxford: Oxford University Press, 2002, esp. chs. 5–6.
Scalise, Charles. “Perichoresis in Gregory Nazianzen and Maximus the Confessor.” (On the development of the verb perichōreō in Gregory the Theologian and the noun perichoresis in Maximus.)
Council of Chalcedon (451). Definition (Horos).
Council of Constantinople III (680–681). Definition.