Not two, but one Christ

The Text

This is the keystone of Part II, and the creed builds it exactly as it built the keystone of Part I. There, faced with three persons and one God, it proceeded by a fenced confession: neither confounding the persons, nor dividing the substance. Here, faced with two natures and one Christ, it does the mirror image: not by confusion of substance, but by unity of person. The two hardest mysteries in Christian doctrine are guarded by complementary rules — in the Trinity, distinguish the persons, do not divide the nature; in Christ, unite the person, do not confuse the natures — and seeing that symmetry is the single most clarifying thing a reader can carry out of this creed.

The verse states the union and fences it on both sides at once. Not two — against every Christology that splits Christ into a divine Son loosely partnered with a human Jesus (Nestorius). Not by conversion of the Godhead into flesh, not by confusion of substance — against every Christology that melts the two natures into a third thing, the humanity swallowed up in the deity (Eutyches). And it gives the direction of the union: the manhood taken up into God, not the Godhead converted down into flesh. The Word does not mutate into a man; the Word takes a complete humanity into his own person. Then the creed risks an analogy — as soul and body make one man, so God and man make one Christ — and the whole later tradition will spend centuries saying both yes and but be careful.

Translation Notes

licet … tamen — “although … nevertheless.” The concessive is the argument’s shape: grant two natures (the creed has just spent verses 30–32 insisting on both, entire) — nevertheless the conclusion is not two of anything that could be counted as a who. Non duo — not two persons, not two sons, not two Christs. This is the anti-Nestorian guard.

non conversione … sed assumptione — “not by conversion … but by taking-up.” Conversio is the turning of one thing into another (water into wine, the divinity into flesh). The creed denies it: the deity is not transmuted; it does not become the humanity (that is Eutyches’ error — the natures mixed into a third). Assumptio is the taking-up: the humanity is assumed, received into the person of the Word. The direction is irreversible and asymmetric — humanitatis in Deum, the manhood into God, not God down into manhood. This is the kernel the later tradition will name enhypostasia: the assumed human nature never exists as its own person; it has its subsistence in the person of the Son.

non confusione substantiae, sed unitate personae — “not by confusion of substance, but by unity of person.” This is Chalcedon in five Latin words. The union is not at the level of substantia (the two natures do not blend; “without confusion, without change”) but at the level of persona — the one hypostasis of the Word, in whom the two natures are united without either being lost. Omnino (“altogether,” “wholly”) rules out the Nestorian residue of a merely close partnership: the unity is total, and it is personal.

the v. 4 / v. 36 mirror. The creed’s own architecture rewards attention here. Verse 4 (the Trinity): neither confounding the persons, nor dividing the substance. Verse 36 (Christ): not by confusion of substance, but by unity of person. The two mysteries are protected by inverse rules — and the inversion is not accidental. It is the creed teaching that the God who is one-substance-in-three-persons is the God who, as the Son, is one-person-in-two-natures: the same divine logic, run in two directions.

nam sicut anima rationalis et caro unus est homo — the analogy and its limit. “For as the rational soul and flesh is one man, so God and man is one Christ.” The creed reaches for the one two-in-one every hearer already is: a human being is a single person of radically unlike components — immaterial rational soul, material flesh — without being two beings. So with Christ. The analogy is genuinely illuminating and genuinely limited, and the tradition has always said both: soul and body compose one nature (a human nature), whereas in Christ the two are distinct natures in one person. The likeness holds for one-from-two; it does not map the nature-relation. The creed offers the picture; it does not absolutize it.

Historical Context

Chalcedon, catechized. Verses 34–37 are the Definition of Chalcedon (451) made memorable: “one and the same Christ … in two natures, without confusion, without change, without division, without separation … the property of each nature being preserved, and concurring in one person and one hypostasis.” Non confusione substantiae, sed unitate personae is that Definition’s heart in the creed’s own Latin.

The two heresies the verse names. Not two answers Nestorius, whose Christology was heard as joining a divine Son and a human Jesus in a unity so loose it amounted to two persons or two sons (the dispute crystallized over Theotokos — was Mary “God-bearer” or only “Christ-bearer”?); condemned at Ephesus (431). Not by conversion / not by confusion of substance answers Eutyches, who taught that after the union there was one nature, the humanity absorbed into the divinity “like a drop of honey in the sea”; condemned at Chalcedon (451). Leo’s Tome is the Western charter behind the creed’s formula.

Cyril, the miaphysites, and an irenic note. Cyril of Alexandria’s insistence on the one Christ (his formula “one incarnate nature of the Word,” read in its Cyrilline sense) shaped the orthodox stress on unity. The churches that did not receive Chalcedon — the Oriental Orthodox (Coptic, Syriac, Armenian, Ethiopian), often called “miaphysite” — were long described as monophysite, but the modern Christological dialogues (the Pro Oriente consultations and the joint declarations of the 1970s–1990s) concluded that Chalcedonian and Oriental Orthodox Christologies confess the same faith in different vocabularies. It is worth saying plainly: the Athanasian Creed is firmly dyophysite — two natures — and the Oriental churches do not receive it, a structural parallel to the Eastern non-reception over the filioque (see [[athanasian-creed/the-father-of-none-the-son-begotten-the-spirit-proceeding]]). The creed is, here too, a creed of the Chalcedonian West.

The unfinished business. The creed states the union and stops; the church kept unfolding it. Leontius of Byzantium and the neo-Chalcedonian settlement articulated enhypostasia (the human nature is anhypostatic in itself, enhypostatic in the Word) — precisely the creed’s assumptione humanitatis in Deum. Constantinople II (553) and III (680–81, the two wills) drew out what perfectus homo (verse 32) and this verse together imply.

Lines of Interpretation

The union is catholic dogma. The live questions: how one person holds two unconfused natures (the perennial question), and the ecumenical relation of the Chalcedonian and miaphysite framings.

Patristic

Tradition: Cyril of Alexandria, On the Unity of Christ; Leo the Great, Tome; the Definition of Chalcedon

The Fathers fixed the union as personal, not natural: one hypostasis, two natures, each preserving its properties. Cyril guarded the unity; Leo guarded the duality of natures; Chalcedon held both.

Strengths

• Secures the one acting subject (so the cross is the act of the Son of God) without losing either nature
• The soul/body analogy gives the untrained mind a real handhold on “one from two”

Weaknesses

• “Two natures, one person” is asserted, not explained — Chalcedon fences the mystery rather than resolving it
• The analogy, pressed, misleads (soul and body make one nature); the Fathers had to keep qualifying it

Scholastic

Tradition: Thomas Aquinas, Summa Theologiae III qq. 2–6, 17

Aquinas locates the union in the suppositum (the person), not the nature: the human nature is real and complete but subsists in the person of the Word (enhypostasia); there is one esse of the one person. He states the soul/body analogy’s limit explicitly, lest it imply a single composite nature.

Strengths

• The most precise account of unitate personae: one subject, the humanity enhypostatic in the Word
• Disarms the analogy’s danger by naming exactly where it stops

Weaknesses

• The metaphysics of suppositum and esse is remote from the worshipper the creed addresses
• Debated even within scholasticism (the question of one or two esse in Christ)

Lutheran

Tradition: the communicatio idiomatum; the genus maiestaticum (Chemnitz, The Two Natures in Christ)

Lutherans affirm unitate personae and press it: because the union is personal and real, the divine attributes are genuinely communicated to the human nature (the genus maiestaticum) — the ground of Christ’s ubiquitous presence in the Supper. The unity is so strong that what is the Word’s is truly the flesh’s in the one person.

Strengths

• Takes unitate personae with maximal seriousness — no merely verbal union
• Yields a high, realist sacramental Christology directly from this verse

Weaknesses

• The Reformed charge the genus maiestaticum with edging toward the confusio substantiae the verse forbids
• The intra-Reformation impasse over the communicatio is unresolved (see [[athanasian-creed/uncreate-and-immeasurable]])

Reformed

Tradition: Calvin, Institutes II.14; the extra Calvinisticum

The Reformed affirm the one person and guard the “without confusion”: each nature retains its own properties, and the Son qua God is not contained or transmuted by the flesh (the extra Calvinisticum). The union is personal; the natures remain unmixed and unconverted — non conversione … non confusione read with the accent on the negatives.

Strengths

• Honors the verse’s anti-Eutychian guards rigorously — the natures never blend
• Keeps secundum divinitatem intact even in the union (continuity with verse 33)

Weaknesses

• The Lutherans charge the extra with loosening unitate personae toward a latent Nestorianism
• Strong “each nature its properties” can sound, in weak hands, like two agents in tandem

Eastern Orthodox (and an Oriental Orthodox note)

Tradition: neo-Chalcedonianism (Leontius, Maximus); the iconodule argument; the modern Chalcedonian–Oriental dialogues

The Chalcedonian East completes the creed’s logic with enhypostasia and the two wills (Maximus), and the holy icon presupposes unitate personae: one can depict the one hypostasis in whom the natures are united. The Oriental Orthodox, non-Chalcedonian, confess (the dialogues conclude) the same union in a miaphysite idiom — and do not receive this dyophysite creed.

Strengths

• Neo-Chalcedonianism gives the fullest account of assumptione humanitatis in Deum (the enhypostatic humanity)
• The modern dialogues show the deepest division here may be substantially verbal — an ecumenical hope

Weaknesses

• The technical settlement (anhypostasia/enhypostasia, dyothelitism) is far past what the creed itself says
• The creed’s firm dyophysitism keeps it, like the filioque, a Western symbol the non-Chalcedonian churches will not own

Modern / Ecumenical

Tradition: the modern abandonment of “two natures” (Schleiermacher, Ritschl); kenotic and Spirit Christologies; the Chalcedonian retrieval (Barth, Church Dogmatics IV; Coakley; Crisp; Sonderegger)

Modern theology has repeatedly judged the two-natures language incoherent and tried to replace it (a Christ defined by God-consciousness, or by the Spirit’s indwelling, or by kenotic self-limitation). The retrieval answers that Chalcedon — and this verse — was never a theory of the union but a rule fencing the gospel: it tells you the ditches (Nestorius, Eutyches) and bids you confess the one Christ between them, exactly as the creed’s own method does everywhere else.

Strengths

• The modern critics rightly press that “two natures” can sound like a paradox asserted, not an account given
• The retrieval rightly recovers Chalcedon’s genre: a regulative fence (like verse 4), not a failed explanation — which is why it has outlasted every replacement

Weaknesses

• The substitutes (God-consciousness, Spirit Christology, strong kenoticism) tend to lose either the not two or the not confused — falling into a modern Nestorianism or a modern Eutychianism
• A retrieval that only says “it’s a rule” can seem to concede the gospel has no positive content here; the verse asserts something true (one Christ), not merely a grammar

Wesleyan Voice

Once more the decisive Wesleyan fact is verbatim retention. The Methodist Articles of Religion, Article II — “two whole and perfect natures … were joined together in one person, never to be divided, whereof is one Christ” — is verses 34–37, Chalcedon intact, carried into American Methodism by the same hand that struck the creed. Wesley deleted the Quicumque; he did not alter one joint of its Christology.

The Wesleyan stake in unitate personae is the atonement itself, and Wesley’s soteriology cannot survive its loss. Sermon 5 (Justification by Faith) and the whole Wesleyan account of the cross require that the one who suffered be one person. If the divine Son and the human Jesus were two (the Nestorian drift), then God did not actually enter our death, and a mere man’s death cannot reconcile the world. If the humanity were swallowed in the deity (the Eutychian drift), then God did not actually take our nature, and we are not actually joined to him in the assumed flesh. Only “one Christ, by unity of person” lets Wesley preach the thing that saves: God himself, in our flesh, for us — the same person both offering the human obedience and giving it infinite, divine worth. Wesley’s “fact, not the manner” applies precisely: confess the one Christ, refuse both the dilution and the collapse, and do not theorize the join.

Charles Wesley compressed the whole doctrine into a phrase no theologian has bettered: Christ “deigns in flesh to appear, / widest extremes to join” (Let earth and heaven combine). That is non conversione … sed assumptione set to music — the widest possible extremes (God and a creature) joined, not by collapsing the distance but by one person spanning it. “Our God contracted to a span, / incomprehensibly made man”; “veiled in flesh the Godhead see.” Where the creed fences the union, the Wesleys sing the joining — and the joining, not the explanation, is the gospel.

Hymnody

This verse is sung as the joining of extremes, and Charles Wesley wrote its definitive line: “He deigns in flesh to appear, / widest extremes to join.” Five words — widest extremes to join — carry the entire hypostatic union: two as unlike as God and dust, made one, unitate personae, without either being lost.

“Let earth and heaven combine” is the verse’s fullest hymn: “our God contracted to a span, / incomprehensibly made man.” “Hark! the herald angels sing”: “veiled in flesh the Godhead see … pleased as man with man to dwell.” “Let all mortal flesh keep silence”: “King of kings, yet born of Mary” — the not two in a single antithesis. “Of the Father’s love begotten” sets the eternal Son in the Virgin’s womb. And “And can it be” states the communicatio idiomatum in a gasp the whole congregation feels: “‘Tis mystery all! The Immortal dies!” — a sentence that is only true, and only sayable, because of unitate personae: the one person, named from the divine nature, truly undergoing what belongs to the human.

The hymnody never explains the union. It does what the creed does — fences it with wonder and then adores the One who is it.

Pastoral and Liturgical Use

This verse is where Christology stops being a doctrine about the gospel and becomes the gospel’s load-bearing wall. A pastor can preach it three ways, and all three matter.

Show the v. 4 / v. 36 mirror, and let it free the anxious. Teach the congregation the symmetry directly: in the Trinity the rule is distinguish the persons, do not divide the nature; in Christ the rule is unite the person, do not confuse the natures. Two mysteries, one God, complementary fences. And then the liberating point: the creed never once tells you how God is three-and-one or how Christ is one-of-two. It tells you the two ditches and bids you worship on the road between them. The Christian is not a person who has solved these; the Christian is a person who has been taught where not to fall and then sent to adore. For the layperson who secretly believes that “real” faith means being able to explain the Incarnation, this is release: you were never asked to explain it. You were asked to confess one Christ and to refuse the two specific errors — and then to worship him.

Name the two heresies in their comfortable modern dress. Nestorius and Eutyches did not die; they went to church. The functional Nestorian keeps two Christs for two purposes: the warm human Jesus for comfort and relatability, the divine Christ for doctrine and Sundays — never quite one person, just two moods. The functional Eutychian keeps a “divine” Jesus whose humanity is scenery: he looked tired but was serenely God inside, his death a performance the deity made painless. Each is pastorally fatal in the same place — the atonement. If the sufferer and the Son of God are two, God never entered your death. If the humanity is decorative, God never took your nature and you are not joined to him. Verse 36 cuts the nerve of both: one Christ, by unity of person — so that the church can say the only sentence that actually saves, God himself, in our flesh, for us. The pastor’s task is to name both half-Christs gently (people hold them out of reverence, not malice) and give back the whole one.

Preach “widest extremes to join” as the shape of grace. The deepest pastoral word here is not the fence but the joining. God did not save humanity from a safe distance by decree. He joined himself — in one person, irreversibly, never to be divided — to the very nature that was lost. The union is not the prelude to the good news; it is the good news. To the person who feels the distance between God and their own small, failing, embodied life is the truest thing about them, verse 36 answers with the truest thing about Christ: that distance — the widest extreme there is — has already been joined, in a person, on purpose, for them. And then take them to the Table, where the church confesses this verse with her hands: “this is my body” — the human flesh given is the flesh of the divine person, and the entire comfort of the sacrament rests on the unitate personae this verse exists to guard. They do not need to understand the union to be fed by it. They need to be told that the broken bread is the one Christ, God and man, given for them — and then to eat.

Further Reading

• John 1:14; 20:28 — the Word was made flesh; my Lord and my God (one Christ, both confessed)
• Romans 9:5; Colossians 2:9 — in him the whole fullness of deity dwells bodily
• 1 Timothy 2:5 — one mediator … the man Christ Jesus (the one person who is both)
• Hebrews 2:14–17; 4:15 — true kinship and true sympathy in the one Christ
• Cyril of Alexandria, On the Unity of Christ; the Twelve Anathemas
• Leo the Great, Tome; the Definition of Chalcedon (451)
• Constantinople II (553); Constantinople III (680–681, the two wills)
• Leontius of Byzantium and the neo-Chalcedonian settlement (enhypostasia); Maximus the Confessor
• Thomas Aquinas, Summa Theologiae III qq. 2–6, 17
• John Calvin, Institutes II.14; Martin Chemnitz, The Two Natures in Christ
• The Chalcedonian–Oriental Orthodox Joint Declarations (Pro Oriente consultations, 1971–1990s)
• Karl Barth, Church Dogmatics IV/1–2
• Sarah Coakley, “What Does Chalcedon Solve and What Does It Not?” (in The Incarnation, ed. Davis et al., Oxford, 2002)
• Oliver D. Crisp, Divinity and Humanity (Cambridge, 2007); Katherine Sonderegger, Systematic Theology, vol. 2 (Fortress, 2020)
• The Articles of Religion of the Methodist Church (1784), Article II
• John Wesley, Standard Sermons, Sermon 5; Explanatory Notes on John 1, Colossians 2
• Charles Wesley, “Let earth and heaven combine”; “And can it be”