Tertia Pars · The Incarnation

Of Christ's Unity of Being

III, q. 17 · Two articles

Prooemium · Thomas's plan for this question

Deinde considerandum est de his quae pertinent ad unitatem in Christo in communi. Nam de his quae pertinent ad unitatem vel pluralitatem in speciali, suis locis determinandum est, sicut supra determinatum est quod in Christo non una est tantum scientia; et infra determinabitur quod in Christo non una est tantum nativitas. Considerandum est ergo primo, de unitate Christi quantum ad esse; secundo, quantum ad velle; tertio, quantum ad operari. Circa primum quaeruntur duo. Primo, utrum Christus sit unum vel duo. Secundo, utrum in Christo sit tantum unum esse.

We must now consider what pertains to Christ's unity in common. For, in their proper place, we must consider what pertains to unity and plurality in detail: thus we concluded (Q. 9) that there is not only one knowledge in Christ, and it will be concluded hereafter (Q. 35, A. 2) that there is not only one nativity in Christ.

Hence we must consider Christ's unity (1) of being; (2) of will; (3) of operation.

Under the first head there are two points of inquiry:

(1) Whether Christ is one or two?

(2) Whether there is only one being in Christ?

  1. 1 Whether Christ Is One or Two?
  2. 2 Whether There Is Only One Being in Christ?

Articulus I

Whether Christ Is One or Two?

Arg. 1 Objection 1

Ad primum sic proceditur. Videtur quod Christus non sit unum, sed duo. Dicit enim Augustinus, in I de Trin., quia forma Dei accepit formam servi, utrumque Deus, propter accipientem Deum, utrumque homo, propter acceptum hominem. Sed utrumque dici non potest ubi non sunt duo. Ergo Christus est duo.

It would seem that Christ is not one, but two. For Augustine says (De Trin. i, 7): "Because the form of God took the form of a servant, both are God by reason of God Who assumed, yet both are Man by reason of the man assumed." Now "both" may only be said when there are two. Therefore Christ is two.

Arg. 2 Objection 2

Praeterea, ubicumque est aliud et aliud, ibi sunt duo. Sed Christus est aliud et aliud, dicit enim Augustinus, in Enchirid., cum in forma Dei esset, formam servi accepit, utrumque unus, sed aliud propter verbum, aliud propter hominem. Ergo Christus est duo.

Further, where there is one thing and another there are two. Now Christ is one thing and another; for Augustine says (Enchiridion xxxv): "Being in the form of God . . . He took the form of a servant . . . being both in one; but He was one of these as Word, and the other as man." Therefore Christ is two.

Arg. 3 Objection 3

Praeterea, Christus non est tantum homo, quia, si purus homo esset, non esset Deus. Ergo est aliquid aliud quam homo. Et ita in Christo est aliud et aliud. Ergo Christus est duo.

Further, Christ is not only man; for, if He were a mere man, He would not be God. Therefore He is something else than man, and thus in Christ there is one thing and another. Therefore Christ is two.

Arg. 4 Objection 4

Praeterea, Christus est aliquid quod est pater, et est aliquid quod non est pater. Ergo Christus est aliquid et aliquid. Ergo Christus est duo.

Further, Christ is something that the Father is, and something that the Father is not. Therefore Christ is one thing and another. Therefore Christ is two.

Arg. 5 Objection 5

Praeterea, sicut in mysterio Trinitatis sunt tres personae in una natura, ita in mysterio incarnationis sunt duae naturae in una persona. Sed propter unitatem naturae, non obstante distinctione personae, pater et filius sunt unum, secundum illud Ioan. X, ego et pater unum sumus. Ergo, non obstante unitate personae, propter dualitatem naturarum Christus est duo.

Further, as in the mystery of the Trinity there are three Persons in one Nature, so in the mystery of the Incarnation there are two natures in one Person. But on account of the unity of the Nature, notwithstanding the distinction of Person, the Father and Son are one, according to John 10:30: "I and the Father are one." Therefore, notwithstanding the unity of Person, Christ is two on account of the duality of nature.

Arg. 6 Objection 6

Praeterea, philosophus dicit, in III Physic., quod unum et duo denominative dicuntur. Sed Christus habet dualitatem naturarum. Ergo Christus est duo.

Further, the Philosopher says (Phys. iii, text. 18) that "one" and "two" are predicated denominatively. Now Christ has a duality of nature. Therefore Christ is two.

Arg. 7 Objection 7

Praeterea, sicut forma accidentalis facit alterum, ita forma substantialis aliud, ut Porphyrius dicit. Sed in Christo sunt duae naturae substantiales, humana scilicet et divina. Ergo Christus est aliud et aliud. Ergo Christus est duo.

Further, as accidental form makes a thing otherwise (alterum) so does substantial form make another thing (aliud) as Porphyry says (Praedic.). Now in Christ there are two substantial natures, the human and the Divine. Therefore Christ is one thing and another. Therefore Christ is two.

Sed contra On the contrary

Sed contra est quod Boetius dicit, in libro de duabus naturis, omne quod est, inquantum est, unum est. Sed Christum esse confitemur. Ergo Christus est unum.

On the contrary, Boethius says (De Duab. Nat.): "Whatever is, inasmuch as it is, is one." But we confess that Christ is. Therefore Christ is one.

Respondeo I answer that

Respondeo dicendum quod natura, secundum se considerata, prout in abstracto significatur, non vere potest praedicari de supposito seu persona nisi in Deo, in quo non differt quod est et quo est, ut in prima parte habitum est. In Christo autem cum sint duae naturae, divina scilicet et humana, altera earum, scilicet divina, potest de eo praedicari et in abstracto et in concreto, dicimus enim quod filius Dei, qui supponitur in hoc nomine Christus, est divina natura, et est Deus. Sed humana natura non potest praedicari de Christo secundum se in abstracto, sed solum in concreto, prout scilicet significatur in supposito. Non enim vere potest dici quod Christus sit humana natura, quia natura humana non est nata praedicari de suo supposito, dicitur autem quod Christus est homo, sicut et quod Christus est Deus. Deus autem significat habentem deitatem, et homo significat habentem humanitatem. Aliter tamen habens humanitatem significatur per hoc nomen homo, et aliter per hoc nomen Iesus, vel Petrus. Nam hoc nomen homo importat habentem humanitatem indistincte, sicut et hoc nomen Deus indistincte importat habentem deitatem. Hoc tamen nomen Petrus, vel Iesus, importat distincte habentem humanitatem, scilicet sub determinatis individualibus proprietatibus, sicut et hoc nomen filius Dei importat habentem deitatem sub determinata proprietate personali. Numerus autem dualitatis in Christo ponitur circa ipsas naturas. Et ideo, si ambae naturae in abstracto praedicarentur de Christo, sequeretur quod Christus esset duo. Sed quia duae naturae non praedicantur de Christo nisi prout significantur in supposito, oportet secundum rationem suppositi praedicari de Christo unum vel duo. Quidam autem posuerunt in Christo duo supposita, sed unam personam, quae quidem videtur se habere, secundum eorum opinionem, tanquam suppositum completum ultima completione. Et ideo, quia ponebant in Christo duo supposita, dicebant Christum esse duo neutraliter; sed quia ponebant unam personam, dicebant Christum esse unum masculine, nam neutrum genus designat quiddam informe et imperfectum; genus autem masculinum designat quiddam formatum et perfectum. Nestoriani autem, ponentes in Christo duas personas, dicebant Christum non solum esse duo neutraliter, sed etiam duos masculine. Quia vero nos ponimus in Christo unam personam et unum suppositum, ut ex praedictis patet, sequitur quod dicamus quod non solum Christus est unus masculine, sed etiam est unum neutraliter.

I answer that, Nature, considered in itself, as it is used in the abstract, cannot truly be predicated of the suppositum or person, except in God, in Whom "what it is" and "whereby it is" do not differ, as stated in the First Part (Q. 29, A. 4, ad 1). But in Christ, since there are two natures, viz. the Divine and the human, one of them, viz. the Divine, may be predicated of Him both in the abstract and in the concrete, for we say that the Son of God, Who is signified by the word Christ, is the Divine Nature and is God. But the human nature cannot be predicated of Christ in the abstract, but only in the concrete, i.e. as it is signified by the suppositum. For we cannot truly say that "Christ is human nature," because human nature is not naturally predicated of its suppositum. But we say that Christ is a man, even as Christ is God. Now God signifies one having the Godhead, and man signifies one having manhood. Yet one having manhood is differently signified by the word "man" and by the word "Jesus" or "Peter." For this word "man" implies one having manhood indistinctly, even as the word "God" implies indistinctly one having the Godhead; but the word "Peter" or "Jesus" implies one having manhood distinctly, i.e. with its determinate individual properties, as "Son of God" implies one having the Godhead under a determinate personal property. Now the dual number is placed in Christ with regard to the natures. Hence, if both the natures were predicated in the abstract of Christ, it would follow that Christ is two. But because the two natures are not predicated of Christ, except as they are signified in the suppositum, it must be by reason of the suppositum that "one" or "two" be predicated of Christ.

Now some placed two supposita in Christ, and one Person, which, in their opinion, would seem to be the suppositum completed with its final completion. Hence, since they placed two supposita in Christ, they said that God is two, in the neuter. But because they asserted one Person, they said that Christ is one, in the masculine, for the neuter gender signifies something unformed and imperfect, whereas the masculine signifies something formed and perfect. On the other hand, the Nestorians, who asserted two Persons in Christ, said that Christ is two not only in the neuter, but also in the masculine. But since we maintain one person and one suppositum in Christ, as is clear from Q. 2, AA. 2, 3, it follows that we say that Christ is one not merely in the masculine, but also in the neuter.

Ad 1 Reply to Objection 1

Ad primum ergo dicendum quod verbum illud Augustini non est sic intelligendum quod ly utrumque teneatur ex parte praedicati, quasi dicat quod Christus sit utrumque, sed tenetur ex parte subiecti. Et tunc ly utrumque ponitur, non quasi pro duobus suppositis, sed pro duobus nominibus significantibus duas naturas in concreto. Possum enim dicere quod utrumque, scilicet Deus et homo, est Deus, propter accipientem Deum, et utrumque scilicet Deus et homo, est homo, propter acceptum hominem.

This saying of Augustine is not to be taken as if "both" referred to the predicate, so as to mean that Christ is both; but it refers to the subject. And thus "both" does not stand for two supposita, but for two words signifying two natures in the concrete. For I can say that "both, viz. God and Man, are God" on account of God Who assumes; and "both, viz. God and Man," are Man on account of the man assumed.

Ad 2 Reply to Objection 2

Ad secundum dicendum quod, cum dicitur, Christus est aliud et aliud locutio est exponenda ut sit sensus, habens aliam et aliam naturam. Et hoc modo exponit Augustinus in libro contra Felicianum, ubi, cum dixisset, in mediatore Dei et hominum aliud Dei filius, aliud hominis filius subdit, aliud, inquam, pro discretione substantiae, non alius, pro unitate personae. Et Gregorius Nazianzenus, in epistola ad Chelidonium, si oportet compendiose dicere, aliud quidem et aliud ea ex quibus salvator est, siquidem non idem est invisibile visibili, et quod absque tempore ei quod sub tempore. Non autem alius et alius absit. Haec enim ambo unum.

When it is said that "Christ is one thing and another," this saying is to be explained in this sense—"having this nature and another." And it is in this way that Augustine explains it (Contra Felic. xi), where, after saying, "In the mediator of God and man, the Son of God is one thing, and the Son of Man another," he adds: "I say another thing by reason of the difference of substance, and not another thing by reason of the unity of person." Hence Gregory Nazianzen says (Ep. ad Chelid. ci): "If we must speak briefly, that of which the Saviour is, is one thing and another; thus the invisible is not the same as the visible; and what is without time is not the same as what is in time. Yet they are not one and another: far from it; for both these are one."

Ad 3 Reply to Objection 3

Ad tertium dicendum quod haec est falsa, Christus est tantum homo, quia non excludit aliud suppositum, sed aliam naturam, eo quod termini in praedicato positi tenentur formaliter. Si vero adderetur aliquid per quod traheretur ad suppositum, esset vera locutio, puta, Christus est tantum id quod est homo. Non tamen sequeretur quod sit aliquid aliud quam homo, quia ly aliud, cum sit relativum diversitatis substantiae, proprie refertur ad suppositum, sicut et omnia relativa facientia personalem relationem. Sequitur autem, ergo habet aliam naturam.

This is false, "Christ is only man"; because it does not exclude another suppositum, but another nature, since terms placed in the predicate are taken formally. But if anything is added whereby it is drawn to the suppositum, it would be a true proposition—for instance, "Christ is only that which is man." Nevertheless, it would not follow that He is "any other thing than man," because "another thing," inasmuch as it refers to a diversity of substance, properly refers to the suppositum, even as all relative things bearing a personal relation. But it does follow: "Therefore He has another nature."

Ad 4 Reply to Objection 4

Ad quartum dicendum quod, cum dicitur, Christus est aliquid quod est pater, ly aliquid tenetur pro natura divina, quae etiam in abstracto praedicatur de patre et filio. Sed cum dicitur, Christus est aliquid quod non est pater, ly aliquid tenetur non pro ipsa natura humana secundum quod significatur in abstracto, sed secundum quod significatur in concreto; non quidem secundum suppositum distinctum, sed secundum suppositum indistinctum; prout scilicet substat naturae, non autem proprietatibus individuantibus. Et ideo non sequitur quod Christus sit aliud et aliud, vel quod sit duo, quia suppositum humanae naturae in Christo quod est persona filii Dei, non ponit in numerum cum natura divina, quae praedicatur de patre et filio.

When it is said, "Christ is something that the Father is"; "something" signifies the Divine Nature, which is predicated even in the abstract of the Father and Son. But when it is said: "Christ is something that is not the Father"; "something" signifies, not the human nature as it is in the abstract, but as it is in the concrete; not, indeed, in a distinct, but in an indistinct suppositum, i.e. inasmuch as it underlies the nature and not the individuating properties. Hence it does not follow that Christ is one thing and another, or that He is two, since the suppositum of the human nature in Christ, which is the Person of the Son of God, does not reckon numerically with the Divine Nature, which is predicated of the Father and Son.

Ad 5 Reply to Objection 5

Ad quintum dicendum quod in mysterio divinae Trinitatis natura divina praedicatur in abstracto de tribus personis, et ideo simpliciter potest dici quod tres personae sint unum. Sed in mysterio incarnationis non praedicantur ambae naturae in abstracto de Christo, et ideo non potest simpliciter dici quod Christus sit duo.

In the mystery of the Divine Trinity the Divine Nature is predicated, even in the abstract of the three Persons; hence it may be said simply that the three Persons are one. But in the mystery of the Incarnation both natures are not predicated in the abstract of Christ; hence it cannot be said simply that Christ is two.

Ad 6 Reply to Objection 6

Ad sextum dicendum quod duo dicitur quasi habens dualitatem, non quidem in aliquo alio, sed in ipso de quo duo praedicantur. Fit autem praedicatio de supposito, quod importatur per hoc nomen Christus. Quamvis igitur Christus habeat dualitatem naturarum, quia tamen non habet dualitatem suppositorum, non potest dici esse duo.

Two signifies what has duality, not in another, but in the same thing of which "two" is predicated. Now what is predicated is said of the suppositum, which is implied by the word "Christ." Hence, although Christ has duality of nature, yet, because He has not duality of suppositum, it cannot be said that Christ is two.

Ad 7 Reply to Objection 7

Ad septimum dicendum quod alterum importat diversitatem accidentis, et ideo diversitas accidentis sufficit ad hoc quod aliquid simpliciter dicatur alterum. Sed aliud importat diversitatem substantiae. Substantia autem dicitur non solum natura, sed etiam suppositum, ut dicitur in V Metaphys. Et ideo diversitas naturae non sufficit ad hoc quod aliquid simpliciter dicatur aliud, nisi adsit diversitas secundum suppositum. Sed diversitas naturae facit aliud secundum quid, scilicet secundum naturam, si non adsit diversitas suppositi.

Otherwise implies diversity of accident. Hence diversity of accident suffices for anything to be called "otherwise" simply. But "another thing" implies diversity of substance. Now not merely the nature, but also the suppositum is said to be a substance, as is said Metaph. v, text. 15. Hence diversity of nature does not suffice for anything to be called "another thing" simply, unless there is diversity of suppositum. But diversity of nature makes "another thing" relatively, i.e. in nature, if there is no diversity of suppositum.

Articulus II

Whether There Is Only One Being in Christ?

Arg. 1 Objection 1

Ad secundum sic proceditur. Videtur quod in Christo non sit tantum unum esse, sed duo. Dicit enim Damascenus, in III libro, quod ea quae consequuntur naturam in Christo duplicantur. Sed esse consequitur naturam, esse enim est a forma. Ergo in Christo sunt duo esse.

It would seem that in Christ there is not merely one being, but two. For Damascene says (De Fide Orth. iii, 13) that whatever follows the nature is doubled in Christ. But being follows the nature, for being is from the form. Hence in Christ there are two beings.

Arg. 2 Objection 2

Praeterea, esse filii Dei est ipsa divina natura, et est aeternum. Esse autem hominis Christi non est divina natura, sed est esse temporale. Ergo in Christo non est tantum unum esse.

Further, the being of the Son of God is the Divine Nature itself, and is eternal: whereas the being of the Man Christ is not the Divine Nature, but is a temporal being. Therefore there is not only one being in Christ.

Arg. 3 Objection 3

Praeterea, in Trinitate, quamvis sint tres personae, est tamen unum esse, propter unitatem naturae. Sed in Christo sunt duae naturae, quamvis sit una persona. Ergo in Christo non est unum esse tantum, sed duo.

Further, in the Trinity, although there are three Persons, yet on account of the unity of nature there is only one being. But in Christ there are two natures, though there is one Person. Therefore in Christ there is not only one being.

Arg. 4 Objection 4

Praeterea, in Christo anima dat aliquod esse corpori, cum sit forma eius. Sed non dat sibi esse divinum, cum sit increatum. Ergo in Christo est aliud esse praeter esse divinum. Et sic in Christo non est tantum unum esse.

Further, in Christ the soul gives some being to the body, since it is its form. But it does not give the Divine being, since this is uncreated. Therefore in Christ there is another being besides the Divine being; and thus in Christ there is not only one being.

Sed contra On the contrary

Sed contra, unumquodque, secundum quod dicitur ens, dicitur unum, quia unum et ens convertuntur. Si ergo in Christo duo essent esse, et non tantum unum, Christus esset duo, et non unum.

On the contrary, Everything is said to be a being, inasmuch as it is one, for one and being are convertible. Therefore, if there were two beings in Christ, and not one only, Christ would be two, and not one.

Respondeo I answer that

Respondeo dicendum quod, quia in Christo sunt duae naturae et una hypostasis, necesse est quod ea quae ad naturam pertinent in Christo sint duo, quae autem pertinent ad hypostasim in Christo sint unum tantum. Esse autem pertinet ad hypostasim et ad naturam, ad hypostasim quidem sicut ad id quod habet esse; ad naturam autem sicut ad id quo aliquid habet esse; natura enim significatur per modum formae, quae dicitur ens ex eo quod ea aliquid est, sicut albedine est aliquid album, et humanitate est aliquis homo. Est autem considerandum quod, si aliqua forma vel natura est quae non pertineat ad esse personale hypostasis subsistentis, illud esse non dicitur esse illius personae simpliciter, sed secundum quid, sicut esse album est esse Socratis, non inquantum est Socrates, sed inquantum est albus. Et huiusmodi esse nihil prohibet multiplicari in una hypostasi vel persona, aliud enim est esse quo Socrates est albus, et quo Socrates est musicus. Sed illud esse quod pertinet ad ipsam hypostasim vel personam secundum se impossibile est in una hypostasi vel persona multiplicari, quia impossibile est quod unius rei non sit unum esse. Si igitur humana natura adveniret filio Dei, non hypostatice vel personaliter, sed accidentaliter, sicut quidam posuerunt, oporteret ponere in Christo duo esse, unum quidem secundum quod est Deus; aliud autem secundum quod est homo. Sicut in Socrate ponitur aliud esse secundum quod est albus, aliud secundum quod est homo, quia esse album non pertinet ad ipsum esse personale Socratis. Esse autem capitatum, et esse corporeum, et esse animatum, totum pertinet ad unam personam Socratis, et ideo ex omnibus his non fit nisi unum esse in Socrate. Et si contingeret quod, post constitutionem personae Socratis, advenirent Socrati manus vel pedes vel oculi, sicut accidit in caeco nato, ex his non accresceret Socrati aliud esse, sed solum relatio quaedam ad huiusmodi, quia scilicet diceretur esse non solum secundum ea quae prius habebat, sed etiam secundum ea quae postmodum sibi adveniunt. Sic igitur, cum humana natura coniungatur filio Dei hypostatice vel personaliter, ut supra dictum est, et non accidentaliter, consequens est quod secundum humanam naturam non adveniat sibi novum esse personale, sed solum nova habitudo esse personalis praeexistentis ad naturam humanam, ut scilicet persona illa iam dicatur subsistere, non solum secundum naturam divinam, sed etiam humanam.

I answer that, Because in Christ there are two natures and one hypostasis, it follows that things belonging to the nature in Christ must be two; and that those belonging to the hypostasis in Christ must be only one. Now being pertains both to the nature and to the hypostasis; to the hypostasis as to that which has being—and to the nature as to that whereby it has being. For nature is taken after the manner of a form, which is said to be a being because something is by it; as by whiteness a thing is white, and by manhood a thing is man. Now it must be borne in mind that if there is a form or nature which does not pertain to the personal being of the subsisting hypostasis, this being is not said to belong to the person simply, but relatively; as to be white is the being of Socrates, not as he is Socrates, but inasmuch as he is white. And there is no reason why this being should not be multiplied in one hypostasis or person; for the being whereby Socrates is white is distinct from the being whereby he is a musician. But the being which belongs to the very hypostasis or person in itself cannot possibly be multiplied in one hypostasis or person, since it is impossible that there should not be one being for one thing.

If, therefore, the human nature accrued to the Son of God, not hypostatically or personally, but accidentally, as some maintained, it would be necessary to assert two beings in Christ—one, inasmuch as He is God—the other, inasmuch as He is Man; even as in Socrates we place one being inasmuch as he is white, and another inasmuch as he is a man, since "being white" does not pertain to the personal being of Socrates. But being possessed of a head, being corporeal, being animated—all these pertain to the one person of Socrates, and hence there arises from these only the one being of Socrates. And if it so happened that after the person of Socrates was constituted there accrued to him hands or feet or eyes, as happened to him who was born blind, no new being would be thereby added to Socrates, but only a relation to these, i.e. inasmuch as he would be said to be, not only with reference to what he had previously, but also with reference to what accrued to him afterwards. And thus, since the human nature is united to the Son of God, hypostatically or personally as was said above (Q. 2, AA. 5, 6), and not accidentally, it follows that by the human nature there accrued to Him no new personal being, but only a new relation of the pre-existing personal being to the human nature, in such a way that the Person is said to subsist not merely in the Divine, but also in the human nature.

Ad 1 Reply to Objection 1

Ad primum ergo dicendum quod esse consequitur naturam, non sicut habentem esse, sed sicut qua aliquid est, personam autem, sive hypostasim, consequitur sicut habentem esse. Et ideo magis retinet unitatem secundum unitatem hypostasis, quam habeat dualitatem secundum dualitatem naturae.

Being is consequent upon nature, not as upon that which has being, but as upon that whereby a thing is: whereas it is consequent upon person or hypostasis, as upon that which has being. Hence it has unity from the unity of hypostasis, rather than duality from the duality of the nature.

Ad 2 Reply to Objection 2

Ad secundum dicendum quod illud esse aeternum filii Dei quod est divina natura, fit esse hominis, inquantum humana natura assumitur a filio Dei in unitate personae.

The eternal being of the Son of God, which is the Divine Nature, becomes the being of man, inasmuch as the human nature is assumed by the Son of God to unity of Person.

Ad 3 Reply to Objection 3

Ad tertium dicendum quod, sicut in prima parte dictum est, quia persona divina est idem cum natura, in personis divinis non est aliud esse personae praeter esse naturae, et ideo tres personae non habent nisi unum esse. Haberent autem triplex esse, si in eis esset aliud esse personae, et aliud esse naturae.

As was said in the First Part (Q. 50, A. 2, ad 3; Q. 75, A. 5, ad 4), since the Divine Person is the same as the Nature, there is no distinction in the Divine Persons between the being of the Person and the being of the Nature, and, consequently, the three Persons have only one being. But they would have a triple being if the being of the Person were distinct in them from the being of the Nature.

Ad 4 Reply to Objection 4

Ad quartum dicendum quod anima in Christo dat esse corpori inquantum facit ipsum actu animatum, quod est dare ei complementum naturae et speciei. Sed si intelligatur corpus perfectum per animam absque hypostasi habente utrumque, hoc totum compositum ex anima et corpore, prout significatur nomine humanitatis, non significatur ut quod est, sed ut quo aliquid est. Et ideo ipsum esse est personae subsistentis, secundum quod habet habitudinem ad talem naturam, cuius habitudinis causa est anima inquantum perficit humanam naturam informando corpus.

In Christ the soul gives being to the body, inasmuch as it makes it actually animated, which is to give it the complement of its nature and species. But if we consider the body perfected by the soul, without the hypostasis having both—this whole, composed of soul and body, as signified by the word "humanity," does not signify what is, but whereby it is. Hence being belongs to the subsisting person, inasmuch as it has a relation to such a nature, and of this relation the soul is the cause, inasmuch as it perfects human nature by informing the body.

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