Commentaria in Summam contra Gentiles, Liber IV

Having set down those things that were necessary for resolving what has been brought forward against the Incarnation, St. Thomas proceeds to their brief resolution ¹.

I. For to the first, it is clear that the consequence is false. Because the Incarnation is not to be understood as if the Word were turned into flesh, or united to a body as a form, but in the manner explained above.

To the second, the consequence is also denied. — To the proof, it is said that through an assumption of this kind no change was made in the Word of God, but only in the assumed human nature, according to which the Word is said to be temporally begotten and born.

Note, from the doctrine of St. Thomas in the Third Book, d. 1 ², a. 1, ad 1, that just as in those things in which there is no mutual real relation, something begins to be said that previously was not said, with no change made in itself, but only in the other (just as something begins to be known not through a change in itself, but through a change in the one who knows); so, since God is not really related to a creature, but is spoken of relatively to it on account of a real relation existing in it, God is said to be newly, or in a certain new way, united to human nature through the Incarnation, not through a change in Himself, but through a change in the assumed human nature.

II. To the third, the consequence is denied. — To the proof, it is said that that assumed premise holds true when the hypostasis has subsistence from nature. But the Word of God does not have subsistence from human nature, but rather draws it to His own subsistence or personality.

To the fourth, it is said that of one subsisting thing there is only one quiddity, or one nature, through which it has esse simpliciter. And thus the Word of God has esse simpliciter through the divine nature alone; but not through the human nature, rather through it He has to be man.

Note that in created things, of one subsisting thing there is only one quiddity, and one nature: because one supposit does not subsist except in one nature, and through it has esse simpliciter. But in Christ there are multiple natures, and multiple quiddities: because His supposit subsists substantially in two natures. But it is true that through one nature alone, and through one quiddity, namely through the divine, He has esse simpliciter: but not through the human, because this is not constitutive of the supposit, as is the divine, but is rather drawn by the supposit itself to the divine personal esse.

III. To the fifth, it is said that certainly the nature through which the Word subsists cannot be other than the very person of the Word. But it is said that He subsists through the divine nature, not through the human. Therefore the reasoning does not follow.

To the sixth, it is clear through the same thing. For it is said that a hypostasis is less simple than the nature through which it is constituted in esse: either in reality, when it is not its nature; or in the intellect, when it is its nature. But the hypostasis of the Word of God is not constituted simpliciter through the human nature, so that it may be through it, but only so that through it He may be this man. Therefore it is not necessary that it be simpler than the Word insofar as He is the Word, but only insofar as He is this man.

Note that for a nature to constitute a supposit simpliciter is for it to be that by which the supposit has that it is absolutely said to be. And because this does not occur except by giving esse formally to the supposit, therefore, for a nature to be said to constitute a supposit, it must give esse to it formally. But for human nature to give to the supposit that it is this man is to be that by which the supposit is called this man. And because this occurs by giving to the supposit that it is a human individual, therefore for it to make the supposit be this man is to be that by which the supposit has that it is a certain individual of man. Because, therefore, human nature does not give to the Word of God the esse through which He is simpliciter, since it does not have its own esse, but is through the esse of the divine person; but gives to the Word Himself that He is a certain human individual, from the fact that it is individual and singular: therefore it is well said that through it it is not given to the Word that He is simpliciter, but only that He is this man.

IV. To the seventh, it is also clear through the same thing. For it is said that it is not necessary for the hypostasis of the Word of God to be constituted simpliciter through designated matter, but only insofar as He is this man: since it is only in this way that He is constituted through human nature.

To the eighth, the consequence is denied. Because the fact that the soul and body in Christ do not constitute another person besides the person of the Word does not pertain to a diminishment of power, but to greater dignity: since everything has a better esse when it is united to something more worthy than itself, than when it exists through itself. — This is made clear by the example of the sensitive soul having a nobler esse in man than in other animals.

To the ninth, it is said that from this soul and from this body in Christ another person is not constituted, but they are assumed to the personality of the Word.

V. To the tenth, it is said first, that this man who is Christ is a certain hypostasis: yet not other than the hypostasis of the Word of God. Whence, when this man is said, the Word Himself is designated by supposit. It is said secondly, if this objection is transferred to the human nature, that not even in Socrates or Plato is human nature a hypostasis: but rather that which subsists in it. It is said thirdly that, although the human nature in Christ is a substance and particular, yet it is not so called according to that meaning by which a hypostasis is a particular substance: because a hypostasis, according to the definition of the Philosopher, is called a substance insofar as a supposit in the genus of substance is called a substance; but not insofar as a quiddity and nature is called a substance. Whence neither are the parts of any substance called particular substances or hypostases in this way: because they are neither per se subsisting, but subsist in the whole; nor are they complete substances.

2. Note that the intention of this third statement is that particular substance can be taken in two ways. In one way, as it is the same as primary substance, divided by the Philosopher against secondary substance: and then a particular substance is the same as a supposit, and per se subsisting, and complete in species. In another way, as it is distinguished against common and universal substance, whether the particular substance subsists per se, or is in another. In the first way, a hypostasis is called a particular substance. But human nature in Christ is not so called, but in the second way: and human nature itself is called a particular substance, and also every single part of it.

VI. To the eleventh, the consequence is denied. Because equivocation is not introduced from a diversity of supposition, but from a diverse form signified by the name. Whence, since this name man, said of Christ and of other men, always signifies the same form, namely human nature, although according to what is taken for Christ it supposits an uncreated hypostasis, while according to what is taken for others it supposits a created hypostasis: it is univocally predicated of them.

To the twelfth, it is said that the hypostasis of the Word is not said to be the supposit of the human nature as if subjected to it as to something more formal, which certainly would have to be said if He were constituted in esse simpliciter through it: but insofar as He draws it to His own substance, just as something is drawn to another nobler thing to which it is united.

To the last, the consequence is denied. Because the Word so assumed human nature that He is truly man, which is to be in the genus of substance. But accidents do not confer substantial esse.

Note that, since esse is taken in two ways, namely for the esse of actual existence, and for the esse of essence, which is the very essence itself; when St. Thomas maintains that the human nature confers substantial esse on the divine Word, esse is taken in the second way. And the sense is that it confers upon Him to be man, insofar as through it the Word is said to be man: just as through human nature Socrates is also said to be man.

Note also that from this response St. Thomas maintains that that proposition, What comes to something after complete esse, comes to it accidentally, holds truth only when such a thing that so comes does not confer substantial esse in the manner explained. But in the Third Part, q. ii, a. 6³; and III Sent., d. vi, a. ult.⁴, it is said that it holds truth unless such a thing is drawn into the communion of that complete esse. Whence in the resurrection the body coming to the rational soul does not come to it accidentally, because it will be assumed to the same esse. But one of these interpretations entails the other. For if something gives to another that it be such substantially, for instance a man, it is necessary that it have the same esse with it. And therefore, if the said proposition does not hold truth when what comes after complete esse confers substantial esse, neither does it hold truth when it is drawn to the communion of that complete esse.