Pohle Vol. IV · Summa III, QQ. 1–26
Christology
The Person of Christ: the Incarnation, the hypostatic union, the two natures, the knowledge and will of Christ. Pohle systematically defends the Chalcedonian formula against ancient and modern errors.
Pohle-Preuss
36 chaptersIntroduction
Table of contents and overview
Preface
Pohle situates Christology within the series: after treating the Fall and the Protevangelium, he turns to the Incarnation itself, distinguishing Christology (the Person of the Redeemer) from Soteriology (the Redemption) and Mariology (Mary's causal relation to both).
The Adamic Origin of the Human Nature of Christ
Christ's human nature is not merely similar to ours but really derived from Adam through the Virgin Mary — a true blood-kinship, established against the Gnostics who denied it, taught by Scripture and the Fathers, and rooted finally in the purpose of the Redemption.
Christology
A dogmatic treatise on the Incarnation, treating the constitutive elements of Christ — His Divinity and His Humanity — and their union in one Divine Person, the Hypostatic Union.
The Adamic Origin of the Human Nature of Christ
Christ's human nature is not merely similar to ours but really derived from Adam through the Virgin Mary — a true blood-kinship, established against the Gnostics who denied it, taught by Scripture and the Fathers, and rooted finally in the purpose of the Redemption.
The Reality of Christ's Sacred Humanity, Against the Docetae
Against the Docetae, who held Christ's body was mere appearance or phantasm, the Church has always taught that Christ's manhood was real and material — a teaching Pohle grounds in repeated conciliar condemnation, in Scripture's own insistently physical language about Christ, and in the Fathers' argument that Docetism, taken seriously, dissolves the Redemption, Christ's Divinity, and reasoned certainty itself.
The Integrity of Christ's Sacred Humanity, Against Arianism and Apollinarianism
Having a real body was not enough: Arius held Christ's manhood was soulless flesh animated only by the Logos, and Apollinaris held Christ had a human soul but no human reason. Against both, the Church defined that Christ possessed a complete human nature — body and rational soul alike — grounding the point in Scripture, in the Fathers both as witnesses and as theologians, and finally in the technical formula of 'two natures, three substances.'
The Passibility of Christ's Human Nature
Christ's human nature was genuinely capable of suffering — bodily infirmity, hunger, weariness, and death, together with real human emotion — against Monophysite claims that His flesh was incorruptible even before the Resurrection. Pohle grounds the point in Scripture and the Fathers, works through the difficult case of St. Hilary (who seems to deny Christ felt pain at all), and closes by carefully bounding which human defects Christ did and did not assume.
The Hypostatic Union: The Chalcedonian Definition
Pohle grounds the whole of Part II in the canon of Chalcedon (A.D. 451) — one and the same Christ, acknowledged in two natures 'without confusion, change, division, separation,' united in one Person and Hypostasis. He reads three distinct claims out of this one sentence: personal unity in two natures, the abiding distinctness of those natures, and the union's absolute inseparability — the three theses the rest of Part II will unfold in turn.
The Hypostatic Union: The Chalcedonian Definition
Pohle grounds the whole of Part II in the canon of Chalcedon (A.D. 451) — one and the same Christ, acknowledged in two natures 'without confusion, change, division, separation,' united in one Person and Hypostasis. He reads three distinct claims out of this one sentence: personal unity in two natures, the abiding distinctness of those natures, and the union's absolute inseparability — the three theses the rest of Part II will unfold in turn.
The Hypostatic Union: Nestorianism and the Church
Nestorius taught that the Logos and the man Jesus are two distinct persons merely indwelling one another, so that Mary is 'Mother of Christ' but not 'Mother of God.' St. Cyril of Alexandria led the Church's response at the Council of Ephesus (431), whose defining term — theotokos, 'God-bearer' — became as central to Christology as homoousion had been to the doctrine of the Trinity.
The Hypostatic Union Demonstrated from Sacred Scripture
Scripture never uses the technical phrase 'Hypostatic Union,' but the doctrine itself is fully Scriptural: the same Christ carries both a divine and a human set of predicates, which is only possible if one Person possesses both natures. John 1:14 and the Philippians 'kenosis' hymn make the case in detail, against both Nestorius and the Modernist claim that this is philosophical speculation rather than the Apostles' own teaching.
The Hypostatic Union: The Patristic Argument
The Fathers before Ephesus (431) condemned Nestorius's error before it was even proposed. Pohle traces the doctrine as simple testimony to Tradition — in the Fathers' own language, in the baptismal creeds' insistence on 'one Lord' — and then in its deeper theological form: the reductio that two hypostases in Christ would make the Trinity a Quaternity, the inverse analogy to the Trinity itself, and the Fathers' answers to pagan mockery of a 'crucified God.'
The Hypostatic Union: Patristic Formulas, Part I
Before the Church settled on 'hypostatic union' as the technical formula, the Fathers tried several others: a 'substantial, physical, natural union' of the two natures; the Logos 'making human nature entirely His own'; and St. Cyril's famously double-edged phrase, 'one incarnate nature of the Word' — orthodox in Cyril's own mouth, but later twisted by the Monophysites into something he never meant.
The Hypostatic Union: Patristic Formulas, Part II
Three more formulas complete the Patristic vocabulary — the two natures 'distinguished in thought only,' the Logos assuming 'flesh through the mediation of a soul,' and finally the classical formula itself, 'hypostatic union,' ratified at Chalcedon. Pohle closes with the word's own strange history: hypostasis meant 'sediment' and 'foundation' before it ever meant 'person,' and its slow technical narrowing is what finally gave the Church a precise word for what Nestorius denied.
The Hypostatic Union: The Dogma in Its Relation to Reason
The Hypostatic Union is a mystery, absolutely indemonstrable by reason — Pohle grounds this in St. Paul's own language about a hidden wisdom no created intellect could reach. But 'indemonstrable' is not 'irrational': reason can refute the objections raised against it, from Bayle's confused worry about personal identity to Celsus's claim that the Incarnation entails change in an immutable God — and every attempt to reason it into full comprehensibility, notably Anton Günther's, has ended in heresy.
The Hypostatic Union: The Mutual Relationship of Nature and Person
Why does Christ's human nature, complete in every way, not amount to a human person? Pohle works through the Scholastic debate over whether 'person' is something really distinct from 'nature' (the Suarezian view) or only virtually distinct from it (the Scotist-Thomist view he favors), and explains how the Logos's own Personhood can simply take the place a human person would otherwise have occupied — without diminishing, only elevating, the humanity it assumes.
The Hypostatic Union: Why the Incarnation of the Logos Does Not Involve the Whole Trinity
If the Divine Essence is identical in Father, Son, and Spirit, why did only the Son become man? Pohle explains that the union terminates in the Logos's Person, not in the Divine Nature as such — so the whole Trinity acts as efficient cause of the Incarnation, but only the Son is its term. He closes with three speculative puzzles the Scholastics loved: could the Father or Spirit have become incarnate instead, could all three Persons have assumed one human nature at once, and could the Logos become incarnate more than once?
The Hypostatic Union: The Controversy Regarding Christ's "Double Existence"
Just as the Logos's Person supplies the place of a human person in Christ, some Thomists argued the Logos's own divine existence supplies the place of a human existence too — leaving Christ's manhood with no created existence of its own. Pohle sides with the majority of theologians against this view: conciliar definitions require Christ's humanity to be complete and undiminished in every human property, existence included, and several Fathers speak explicitly of Christ possessing a genuinely human existence alongside His divine one.
The Hypostatic Union: The Phrase "Hypostasis Christi Composita"
May Christ's Hypostasis be called 'composite'? Tiphanus called the phrase dangerous, but Pohle shows it is orthodox once 'Hypostasis Christi' is read formally (as Christ Himself, the Incarnate Word) rather than materially (as the simple Person of the Logos alone) — closing Article 2 with the axiom that Christ is 'one thing from several,' not 'a whole made of parts.'
The Inconfusion of the Two Natures in Christ: Against Monophysitism
Eutyches swung to the opposite extreme from Nestorius, holding Christ has only one nature — a blend of divine and human — rather than two, unmixed. Chalcedon (451) defined the mean between both errors: Christ exists in two natures 'without confusion, without change, indivisibly, inseparably.' Pohle grounds this in Scripture, the Fathers before Chalcedon, and a careful audit of the analogies (body-and-soul, mixed liquids, light and air) the Fathers used and where each one breaks down.
Two Wills in Christ, Against Monothelitism
Sergius of Constantinople tried to reunite Monophysites to the Church with a compromise formula, 'one will and one operation' in Christ — a Monophysitism in disguise, condemned at the Sixth Ecumenical Council (680-681) after Pope Honorius's own ambiguous handling of the affair became a byword. Pope Agatho's dogmatic letter marshals Christ's own words in Gethsemane, the Fathers, and the axiom that operation follows nature, not person, to establish that Christ has two complete wills, human and divine, cooperating without contradiction.
Christ's Theandric Operation
Following St. Maximus Confessor, Pohle sorts Christ's acts into three kinds — purely divine, purely human, and 'theandric' (God-and-man-together), like healing by touch and a word — while insisting the theandric never means some third, hybrid nature of acting. In the fullest sense, even Christ's hunger and suffering count as theandric, since it is the Logos Himself who hungers and suffers in His human nature, and it is precisely this that made the Passion redemptive.
The Inseparability of the Two Natures in Christ
The Hypostatic Union began at Christ's conception, never lapsed even for an instant — not even during the three days in the tomb — and will never end. Pohle works through the fine points this raises: whether Christ's blood, shed on the Cross, stayed hypostatically united to the Logos during the triduum mortis, what that implies about relics of the Precious Blood, and why Christ's eternal kingship rules out any future separation of the natures.
Christ's Freedom from Original and Personal Sin
The first two theses on Christ's holiness: as man, He was conceived free of original sin and its aftermath, concupiscence, since original sin passes only through ordinary generation and Christ was conceived by the Holy Ghost; and He committed no personal sin whatsoever, a truth Pohle grounds in Ephesus and Chalcedon, in Isaiah's prophecy of the sinless Messias, and in Christ's own unmatched challenge to His accusers: 'Which of you shall convince me of sin?'
Christ's Impeccability
Beyond simply never sinning, Christ as man was incapable of sinning at all — a truth Pohle grounds in the Hypostatic Union itself, following St. Thomas against Günther's shallow reading and Durandus's theory of merely external prevention. This raises theology's hardest problem about Christ: if He could not sin, was His will genuinely free when He accepted death? Pohle surveys four rival Scholastic solutions without fully resolving the tension, calling it one of the gravest problems in the field.
Christ's Substantial Sanctity
Beyond sanctifying grace, Christ's human nature was made holy simply by being united to the Logos — 'the oil of gladness above thy fellows' that gives Him His very name, 'the Anointed.' Pohle explains how this substantial holiness can be communicated to a creature without collapsing into Monophysitism, and surveys the Scholastic dispute over whether it is the Logos's Person or His Divine Nature that formally sanctifies Christ's humanity.
Christ's Fullness of Habitual Grace
Beyond the substantial holiness of the Hypostatic Union, Christ's human soul possessed created, accidental holiness too — sanctifying grace, in a fullness greater than any other creature could ever receive. Pohle grounds this in John's Prologue ('full of grace and truth ... of his fulness we have all received') and in the Fathers, arguing that the same homogeneous grace by which we are justified must have first existed, superabundantly, in Christ Himself.
Christ's Grace of Headship (Gratia Capitis)
Christ's fullness of grace was infused entire at the instant of His conception — His growth 'in wisdom and age and grace' was manifestation, not increase. Beyond His personal holiness, the Hypostatic Union made Him Head of the whole created order: of the Church in the fullest sense, of the angels by dignity and dominion though not by shared nature, and Lord — if not, properly, Head — even of inanimate creation.
Christ's Beatific Vision: The Scriptural and Patristic Evidence
Christ's human soul, from the first moment of its existence, possessed the beatific vision of God — meaning He was, in the technical phrase, 'wayfarer and possessor at once.' Pohle opens the treatise on Christ's human knowledge here, working through the thin but real Scriptural case (especially John 1:18 and 8:55) and the sparser Patristic record, including St. Fulgentius's valuable but overreaching attempt to treat the question directly.
The Theological Case for Christ's Beatific Vision
Three theological arguments for Christ's earthly beatific vision: the Hypostatic Union itself demands it as grace's highest consummation; His headship over all creatures requires Him to already possess what He communicates to others; and only the beatific vision explains how Christ could be infallibly conscious of His own Messiahship and Divinity from the very first, rather than holding it merely by faith. Pohle closes by carefully bounding this vision's extent — it does not amount to full comprehension of the Divine Essence, which remains impossible even for the blessed.
Christ's Infused Knowledge: What It Is, and the Scriptural Case
Beyond the beatific vision, Christ's soul possessed infused knowledge — the connatural mode of knowing proper to angels, granted to a human soul (as it was to Adam and Solomon) as a preternatural gift. Pohle argues this from Isaiah's prophecy that the 'spirit of wisdom and understanding' would rest on the Messias, and from John the Baptist's testimony that God gives Christ the Spirit 'not by measure.'
Christ's Infused Knowledge: The Agnoetae Controversy
A sixth-century sect, the Agnoetae, claimed Christ's human nature was ignorant of certain things, notably the date of the Last Judgment — a heresy Pope St. Gregory the Great traced back to Nestorianism at root. Pohle works through the Fathers' careful, sometimes strained handling of Mark 13:32 ('the Son knoweth not the day'), and closes with the argument that Christ, as Head of the angels themselves, must have known them in their own proper mode of angelic knowledge.
Christ's Acquired, Experimental Knowledge
Beyond the beatific vision and infused knowledge, Christ's soul possessed genuine acquired knowledge too — gained the ordinary human way, by abstracting concepts from sense experience. Denying this would tip into Docetism, since a real human intellect (agent and possible alike) demands its own proper operation. Pohle surveys the rival Scholastic theories on just how far this properly human, experiential knowledge extended, and closes the whole treatise on Christ's human knowledge here.
The Adorableness of Christ's Humanity: Preliminary Notions and Thesis I
Pohle opens the book's final Article by defining the technical vocabulary of worship — latria, dulia, hyperdulia, absolute versus relative worship — before establishing the first thesis: Christ, as the God-man, is owed the same single act of divine adoration as the unincarnate Logos, since to worship Him differently as man than as Son of God would be to fall back into Nestorius's error of two persons in Christ.
Christ's Sacred Humanity as Object of Divine Worship
Christ's human nature is worshipped with divine adoration in itself — but never for its own sake, only because it is hypostatically united to the Logos. Pohle grounds this in Scripture, in the Fathers' insistence that we cannot separate the flesh from the Logos when we adore Him, and in the Eucharistic worship of Christ's body and blood, before closing with the disputed question of whether Christ's human excellences considered on their own would merit only the lesser worship of hyperdulia.
The Adorableness of Christ's Body and the Devotion to the Sacred Heart
The final thesis of the book: not only Christ's humanity as a whole, but its individual parts — His soul, His Precious Blood, His Five Wounds, and above all His Sacred Heart — are entitled to full divine worship, since each is inseparably united to the Logos. Pohle traces the devotion to the Sacred Heart from Margaret Mary Alacoque through its papal approval, and insists, against a rationalizing 'symbolic' reading, that it is the real, physical Heart of Jesus that the faithful adore.
Glenn's Tour of the Summa
25 questionsGlenn's chapter-by-chapter précis of the Summa Theologica, with links to the full Latin–English text at New Advent.
Q.1 Fitness of the Incarnation Q.2 The Union of the Word and the Flesh Q.3 The Person Assuming Human Nature Q.4 The Nature Assumed Q.5 Elements of the Nature Assumed Q.6 Order of the Elements Assumed Q.7 The Grace of Christ as a Man Q.8 The Grace of Christ as Head of the Church Q.9 Knowledge in Christ Q.10 The Beatific Knowledge in Christ Q.11 Christ's Infused Knowledge Q.12 Christ's Acquired Knowledge Q.14 Deficiencies in the Body of Christ Q.15 Limitations or Deficiencies in Christ's Human Soul Q.16 Consequences of the Hypostatic Union Q.17 The Oneness of the Being of Christ Q.18 The Unity of Will in Christ Q.19 The Unity of Operation in Christ Q.20 The Subjection of Christ to God the Father Q.21 The Prayer of Christ
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