D. 5 - Divine generation and divine essence

Division of the text

Here the Master presents a question about the names signifying the essence in the abstract, whether some of them can stand to the generation of the Son as its subject or terminus. And he does three things about this. First he states the question; second, he answers it, at in consensus with Catholic expounders, we say regarding this; (Sent. I, 5.1(15).1.) third, he confirms this answer, at therefore, it is not to be said that the Father generated a divine essence. (Sent. I, 5.1(15).2.)

And the third is divided into two parts.

In the first, he shows that the divine essence does not relate to generation as its terminus, so that it might be said to be generated.

In the second, he shows that it does not relate to it as its subject either, so that it might be said to be generating, at in the same way, it is not to be asserted that the divine essence generated the Son. (Sent. I, 5.1(15).6.)

The first part is divided into two:

in the first, he lays out the proof;

in the second, he excludes the contrary, at Augustine seems to state the contrary to this. (Sent. I, 5.1(15).5.)

He shows the first in three ways.

One is as follows: everything in the divine that generates anything is spoken of as relative to it, and vice versa. Therefore if the Father generates the divine essence, then the essence is being spoken of as relative to the Father, and thus it would not signify the divine substance, according to Augustine. (Sent. I, 5.1(15).2; Augustine, On the Trinity, bk. 5, ch. 7 (CCSL 50; PL 42:866).)

The second is as follows: the Father is the divine essence. Therefore if the Father generates the divine essence, the Father would generate that which he himself is—which cannot be, according to Augustine, at also, since God the Father is divine essence, if he were to be the begetter of it, he would also be the begetter of that which he himself is. (Sent. I, 5.1(15).3.)

The third is as follows: the Father has existence through the divine essence. Therefore if the Father were to generate the divine essence, the Father would have existence through what is generated from his very self—whereas the contrary seems more true; and this is at also, if the Father is the begetter of the divine essence, since by the same divine essence he both is and is God, it follows that, by that which he begets, he both is and is God. (Sent. I, 5.1(15).4.)

In the same way, it is not to be asserted. (Sent. I, 5.1(15).6.) Here he proves the other part of the question, that the essence is not the supposit of the act of generation as the one generating. And this is done in two ways, that is, that neither does the essence generate the essence, nor does it generate the Son. And it is divided into two: first, he lays out the proof for both; second, he presents the contrary, at but what Augustine says . . . appears to be the contrary. (Sent. I, 5.1(15).7.)

This latter is divided into two parts. In the first, he presents the opposing arguments showing that the essence generates the essence. In the second, he shows that the essence would generate the Son, at it is also said, and it is frequently said in the Scriptures, that the Father begot the Son from his own substance. (Sent. I, 5.1(15).12.)

As regards the first, he does two things.

First, he makes the objection from the authorities of Augustine;

and second, from the authorities of Hilary, at but what Hilary says . . . appears to be contrary to this. (Sent. I, 5.1(15).9.)

Each of these is divided into an objection and a resolution. Likewise also the following part is divided into objection and resolution.

To understand this part one asks about three things:

first, whether the essence stands to the generation of the Son as the generator; (Q. 1.)

second, whether it stands as that of which there is generation; (Q. 2.)

third, whether it stands as that which is the terminus of the generation. (Q. 3.)

Question 1

Whether the essence stands to generation as generator

About the first, two things are asked:

first, whether the essence generates;

second, given that it does not, whether it is the same way with all the other essential names.

Article 1

Whether the essence generates

To the first we proceed as follows. (Parallel text: ST I.39.3.) It seems that the essence generates.

Obj. 1: For the opposition of affirmation and negation is greater than the opposition of relation. But in the divine an opposition of relation makes one person not another. Therefore a contradiction would do this much more. But the person of the Father is the generator. Therefore, if the essence did not generate, the Father will not be the essence—which is impossible.

Obj. 2: Furthermore, whatever is predicated of something can stand for it. But the essence is predicated of the Father, and truly. Therefore it can stand for the Father, and thus it can receive the Father’s predication. Therefore it can be granted that the essence generates.

Obj. 3: Furthermore, if the essence is the Father, then it is the Father of the Son. But relatives are spoken of as reciprocal. Therefore the Son will be the Son of the essence. Therefore the essence generates.

Obj. 4: Furthermore, the essence is the generating reality. But a generating reality is a generator. Therefore the essence is the generator.

Obj. 5: Furthermore, as the essence stands to the person, so does the person to the essence. But the attributes of the essence—such as power, goodness, and the rest—are predicated of the person. Therefore the person’s properties are also predicated of the essence. Therefore it can be said that the essence is a generator.

On the contrary is what is shown in the arguments the Master lays out. (Sent. I, 5.1(15).6.)

I answer that in created things acts belong to supposits, and the essence does not act; rather, it is a principle of the act in the supposit. For humanity does not generate; rather, Socrates does, by the power of his nature. Now, in created things the essence is really different from the supposit, so no act properly is predicated of the essence, except causally. However, in the divine the essence is really not different from the supposit; rather, they differ only in account, that is, as regards the mode of signifying, since the supposit is distinct, and the essence is common. Therefore, in the divine, whatever things are predicated of the supposit, but not according to the mode by which it differs from the essence, are predicated also of the essence. For we say that the essence creates, and governs, and the like. But an act that is said of the supposit according to the mode by which it does differ from the essence cannot be predicated of the essence. And an act like this is the act of generating, which is predicated of the supposit of the Father insofar as he is distinct from the supposit of the Son. Whence one should not grant that the essence generates, but that the Father generates by the power of the essence or nature. This is also why Damascene says (John Damascene, On the Orthodox Faith, bk. 1, ch. 8 (PG 94:814).) that generation is the divine nature’s enduring activity.

Reply Obj. 1: Affirmation and negation are said to be most opposed to each other because no agreement is implied in them. For in privative opposites an agreement in subject is implied, since they are naturally apt to occur in the same thing, and in contrary relatives there is agreement in genus, since they are in the same genus. Whence in both oppositions each extreme is signified through the mode of being and a certain nature. Now, that wherein is found no mixture with its contrary is the greatest and first in that genus, and the cause of all the others. And therefore the opposition of affirmation and negation, in which is mixed no agreement, is the first and greatest opposition, and the cause of every opposition and distinction. And therefore affirmation and negation must be included in every other opposition, just as the first is included in the posterior. Whence more things are required for the other oppositions than for the opposition of contradiction, since they are based on an addition to it. Whence it is not necessary that, if contrariety is found only in things that are really diverse, then affirmation and negation is also found in things that are really diverse; indeed, even a distinction of account is enough for affirmation and negation, since every distinction, as was said, includes affirmation and negation, and such a distinction, that is, one of account, is that between the essence and the person. But relative opposites sometimes require real diversity or distinction, and such are what distinguish the divine persons. But sometimes they require only a distinction of account, as when one says that a thing is the same as itself. And this will be explained better in the treatment of relations. (In I Sent., d. 26, q. 2, a. 1.)

Reply Obj. 2: The essence is not predicated of the supposit by reason of the mode of signifying in each of them, but by reason of the lack of real difference between them, on account of the simplicity of the divine nature. And therefore it need not stand for the Father.

Reply Obj. 3: When one says that the essence is the Father, the expression is of two sorts, because the word “Father” can be taken, as it were, adjectivally, so that places its form on the essence—and in this way it is false. For the personal properties do not determine the essence. Or it can be taken substantively, and then “Father” in the predicate stands for the person of the Father—and in this way it is true. Nor must its converse be put this way: therefore the Son is the Son of the essence; rather, it would be: therefore the Son is the Son of the Father, who is the essence.

Reply Obj. 4: When one says, “the essence is the generating reality,” the word “reality” can stand for the essence or the person. If it stands for the essence, then it is false, since thereby the adjective “generating” would place its form on the essence. But if it stands for the Person, then it is true, and then “therefore the essence is the generating” does not follow, since then the adjective’s form is not placed on the same thing.

Reply Obj. 5: Since “essence” and “person” differ in mode of signifying, what is predicated of a person by reason of the mode of signifying, insofar as it is distinguished from the essence, is not predicated of the essence—for example, generating, generated, and things of this sort. Similarly on the side of the essence: for what is predicated of the essence by reason of the mode of signifying, by which it differs from the distinct supposit, is not predicated of the supposit—for example, the essence is common to the three, yet this commonness cannot be said of any one of the persons.

Article 2

Whether the act of generating can be predicated of any of the essential names

To the second we proceed as follows. (Parallel texts: above, d. 4, q. 1, a. 2; ST I.39.4.) It seems that the act of generating is predicated of none of the essential names.

Obj. 1: For just as the three persons are one essence, so also are they one God. But, by the Master’s reasoning, (Sent. I, 5.1(15).6.) one cannot say that the essence generates, lest it indicate a distinction of essence. Therefore likewise one cannot say God generates, lest a plurality of gods follow.

Obj. 2: Furthermore, “person,” “hypostasis,” and “substance” are not relative terms. But according to the Master, the essence cannot be said to generate because “essence” is not a relative term. Therefore likewise neither does a person or hypostasis generate.

Obj. 3: Furthermore, the names “nature,” “goodness,” and the like are just as abstract as “essence.” Therefore, if “essence” on account of its mode of signifying in the abstract cannot generate, then it seems that neither do the others.

On the contrary is what is shown by the many authorities in the text. (Sent. I, 5.)

I answer that, as was said in the previous article, generating belongs properly to the supposit as distinct from the others. And therefore the more a name approaches the distinct supposit, so much more truly can the act of generating be predicated of it. Whence “the Father generates” is the most proper, because the name “Father” is imposed from his distinguishing property. Likewise one can say, “a person generates,” since the name “person” is imposed from property in common, which is called “personhood.” And consequently, “God generates” is said less properly, since even though it contains the supposit in itself, still it does not contain a distinct supposit, nor is the name imposed from a distinguishing property, but rather from the common essence.

Moreover, in all abstract names there is also an order. For some signify an order to act, for example, “power,” “goodness,” “light,” “nature,” and the like, and because acts belong to supposits, therefore with such one finds sayings such as “wisdom generates,” or “the nature generates.” Nonetheless expressions of this sort should not be extended further, but should be understood in a pious way. Now, some names do not signify an order to action, but rather are imposed according to the name’s account, from the act of standing under it, like “substance.” Whence this name “substance” still approaches the account of a supposit, whereas the name “essence” is wholly remote from the account of a supposit, so least of all can one say, “the essence generates.” Nevertheless, if it were so found, it would have to be expounded as “the essence, that is, the Father who is the essence, generates.”

Reply Obj. 1: The name “God” indeterminately includes within itself the supposit, and by reason of what the name is imposed from, it includes within itself the nature. Whence, by reason of the mode of signifying it is, as it were, an intermediate between the essence and a distinct person. And therefore by reason of its indeterminacy, the mode of the essence is not repugnant to it, nor is the mode of a distinct person, by reason of its supposit. Therefore one can say, “God generates,” and “‘God’ is common to the three persons.”

Reply Obj. 2: In the divine, the relative is spoken of in many ways. For most properly the relative is what according to its name refers to another, like “Father.” However, another relative is what follows or causes a relation, like “generation” and “to generate.” Moreover, a still different relative is what implicitly contains a relation within itself, as “Trinity” implicitly contains persons distinct by relation; and this name “person” includes within itself a distinguishing relation. Moreover, something else can be called relative insofar as it is put down in place of a relation, like “God,” and even certain abstract names, the account of which was given in the body.

Reply Obj. 3: “Essence” is of greater abstraction than is “goodness” or “wisdom,” because even though they equally abstract from the supposit, still “essence” over and above this abstracts even from act, whereas the other two signify an order to act.

Question 2

Whether the essence is that of which there is generation

Next it is asked whether the essence stands to the generation as that of (The Latin de could be translated as either “from” or “of” (and in some contexts as “about”). Given Aquinas’s explanation in the corpus, “of” seems to be the sense he is stressing, even though “from” might seem to be more natural of a translation in this context.) which there is generation. And two things are asked about this:

first, whether the Son is generated of the Father’s substance;

second, whether he is generated out of nothing.

Article 1

Whether the Son is generated of the Father’s substance

To the first we proceed as follows. (Parallel texts: In III Sent., d. 11, a. 1; ST I.41.3.) It seems that the Son is not generated of the Father’s substance.

Obj. 1: For every preposition is transitive, and transitivity requires diversity or distinction. Therefore, since the Son is not distinguished from the Father’s essence, he cannot be said to be born of his essence.

Obj. 2: Furthermore, just as human nature stands to Socrates, so does the divine essence stand to the Son. But Socrates cannot be said to be of the human essence. Therefore neither can the Son be of the Father’s essence.

Obj. 3: Furthermore, “of” always indicates an order. But between the Son and the divine essence there is no order of time, or of nature, since the essence is not the generator, the Father is, or of causality. Therefore it seems that he is in no way of the Father’s essence.

Obj. 4: But you might say that this is said on account of the consubstantiality of the Father and the Son.

On the contrary, just as the Father’s essence is the Son’s essence, so too the entire essence of the Son is in the Father. Therefore, for the same reason as the converse, one can say that the Father is of the Son’s essence.

On the contrary is what is shown through the authorities in the text. (Sent. I, 5.)

I answer that the preposition “of” properly designates a principle and consubstantiality, whereas the preposition “from” designates only the order of a principle. Whence whatever is said to be of something is also from it, but not vice versa, as will be explained below. (In I Sent., d. 36, q. 1, a. 3, ad 5; d. 25, exposition of the text; see also Sent. I, 36.5(163).1.) This is why the preposition “from” sometimes notes only an order of time, like day comes from night, but sometimes an order of the active principle, like works of art are from the artisan, and sometimes the material principle, like the knife is made from iron. But “of,” since it notes consubstantiality, always notes either the material principle or a consubstantial agent, as when we say that a man is begotten of his father, since the generation occurs through a separation from his substance.

And in this way the Son is said to be of the Father and of the Father’s essence. Yet he is of the Father as of a generator, and of his essence as of the communicated principle of generation. This is also why it approaches a likeness with matter, if one were to remove from matter all there is of imperfection and this alone were to remain of the conditions of matter: that it endures in the thing and through it the thing subsists. And this is especially the case with a thing made by art, which is in the genus of substance on account of its matter and not on account of its form, as the Commentator says. (Averroes, Commentary on Aristotle’s On the Soul, bk. 2, comm. 4.)

Reply Obj. 1: “Of,” as has been deduced, signifies consubstantiality and order to a principle, and the substantiality looks to the essence, while the order, by reason of its transitivity, looks to the generating person. For we do not say that the Son is of the essence, but that he is of the essence of the Father. And therefore there need not be a distinction of the Son from the essence, but only from the Father.

Reply Obj. 2: Likewise, Socrates is said to be born of his father’s nature or from his substance just as the Son of God is, yet in a different way. For the Son of God is of the entire substance of the Father, whereas Socrates is from part of his father’s substance. Further, they differ in another way, for Socrates subsists not only through his essence but also through his matter, whereby the nature of humanity is individuated in him. But the Son of God subsists through the Father’s essence, since the essence is not a part of the Son, but the whole that is the Son.

Reply Obj. 3: This should be answered in the same way as was the first.

Reply Obj. 4: Not only consubstantiality is noted in “of,” but also the order to the principle. And this would not be preserved if one were to say, “the Father is of the Son’s essence.”

Article 2

Whether the Son is from nothing

To the second we proceed as follows. It seems that that Son is generated from nothing.

Obj. 1: For what is not from previous matter is said to be from nothing. But the Son is like this, since he is not of something as of matter. Therefore and so on.

Obj. 2: Furthermore, whatever has existence only from another, is not a being in and of itself, since between is and is not there is no middle. But the Son has existence only from the Father, and therefore of himself he does not have existence. But every such thing, according to Avicenna, (Avicenna, Metaphysics (al-Ilāhiyyāt), bk. 7, ch. 7. Avicenna’s Metaphysics is itself a section of The Book of Healing (al-Shifa’).) is from nothing. Therefore the Son is from nothing.

On the contrary, everything that is from nothing is created. But the Son is uncreated. Therefore and so on.

Furthermore, according to Damascene, (John Damascene, On the Orthodox Faith, bk. 1, ch. 3 (PG 94:795).) everything that is from nothing can be turned into nothing. But the Son is not of this sort. Therefore and so on.

I answer that it is different to say something is not from something and to say something is from nothing. For when one says it is not from something as from matter, nothing is being asserted, and this way of speaking fits the Son of God. However, when one says it is from nothing, an affirmed order to nothing remains. But something has an order to nothing in two ways: an order of time and an order of nature. The order of time is such that before the being was not, and after the being is—and this belongs to nothing eternal. The order of nature is when something has existence depending on another, for such a thing, on its part, has only non-existence, since its entire existence depends on another, and what exists from its very self naturally comes before what exists due to another. And therefore, supposing that the heavens and the like were from eternity, still it is true to say that the heavens are from nothing, as Avicenna proves. Now, in neither way does the Son have an order to nothing, for he has no order of time, since he is eternal, and he has no order of nature, since his existence is absolute, not dependent on another.

Reply Obj. 1: Although he is not of matter, still it does not follow that he is not of something, since he is of the substance of the Father. Even were this set aside, it would still not follow that he would be from nothing, as was said, since the Father is not of something, and yet he is not from nothing.

Reply Obj. 2: Although the Son has his whole existence from another, still his existence is not dependent. For he receives numerically the same existence from the Father that the Father himself has, and therefore his existence is not dependent, like the existence of what is created, which would fall into nothingness; nor is it possible, nor is it from nothing, all of which would necessarily follow if he were to receive a numerically different existence.

Question 3

Whether the essence is the terminus of the generation

Article 1

Whether the essence is the terminus of the generation

Next it is asked whether the essence is the terminus of the generation. (Parallel text: ST I.39.5.) And it seems not.

Obj. 1: Since generation is between two termini, the terminus from which the generation starts and the terminus to which the generation goes. But the Son’s generation has no terminus-from-which, since he is not from non-being. Therefore he also has no terminus-to-which.

Obj. 2: Furthermore, whatever is the terminus of a generation is generated through itself or incidentally: through itself as the very thing generated, incidentally as its form. But the essence is in no way generated, just as neither is it the generator, since a distinction would then result. Therefore it is not the terminus of the generation.

Obj. 3: Furthermore, if it were the terminus, this would be only insofar as the essence is received through the generation. But the Son does not receive the essence. Therefore the essence is not the terminus of the generation. Proof of the middle premise: since receiving does not befit the three persons, it is a notional act, whereas no notional act is terminated at the essence, as it is clear that the Father does not generate the essence. Therefore neither does the Son receive the essence.

On the contrary, what the generation occurs in is the terminus of the generation. But Hilary says that the only begotten birth subsists in the unbegotten nature. (Hilary, On the Trinity, bk. 9, ch. 53 (CCSL 62A; PL 10:324).) Therefore the nature or essence is the terminus of the generation.

Furthermore, generation is found in the divine according to what belongs to perfection in generation, as was said above. (Above, d. 4, q. 1, a. 1.) But the whole perfection of a generation is from its terminus-to-which. Therefore in the divine generation it is the terminus-to-which. But this is nothing other than the essence. Therefore and so on.

I answer that the terminus of generation in created things can be taken in two ways, just as can its principle. For the one generating is called the principle of the generation, and the one generated corresponds to this principle as its terminus. Also, that from which the generation begins is called the principle of the generation, and in this way the principle or beginning of the generation is the privation of the form to be brought forth. And the terminus opposite this principle is the form brought forth through the generation. For example, in whitening the terminus-from-which is blackness, and the terminus-to-which is whiteness. Likewise, in the divine the terminus of the generation (even though there is no action or change here) can be taken in two ways: the one generated, and this is the Son, or the essence received by the Son through his generation.

Reply Obj. 1: Generation and every motion whatsoever has its entire imperfection from the terminus-from-which, which is the privation or the contrary that includes the privation. And therefore in the divine generation there is no terminus-from-which, but only a terminus-to-which, from which arises the entire perfection of the generation.

Reply Obj. 2: The divine essence is not begotten in the Son either through itself nor incidentally, for the same essence is in the begetter and the begotten. However, if the divine essence were divided, then it would necessarily follow that it would be begotten incidentally, although not through itself, just as happens in created things.

Reply Obj. 3: Although receiving is a notional act, still it can be terminated at the essence. This is clear because in the divine generation, just as in any other generation, one can consider three things: the generator, the one generated, and the nature communicated through the generation. Therefore notional words can designate the relation of the generator to the one generated, like “to generate,” or that of the generator to the essence, like “to give,” or of the one generated to the essence, like “to receive,” or of the one generated to the generator, like “to be born.”

Therefore one must note that, because every notional word signifies the act of a person as distinct, it always must come from a distinct person. And therefore no such word goes forth from the essence, such that the essence might be said to generate or give notionally, or to receive or to be born. However, words that designate the relation of the generator to the essence, or that of the one generated to the essence, do not terminate at the essence, for they are not distinctive on that side. And “to receive” and “to give” are words like this. But words that designate the relation of the one generated to the generator or vice versa are distinct on both sides. And therefore the essence can be joined to them from neither side, since the essence does not generate, nor does the Father generate the essence. And this is clear from the signification of the words, since the one generating, as generating, is distinguished from the one generated and vice versa. But the one giving is indeed distinguished from the one to whom he gives but not from what he gives, since sometimes someone can give his very self. Likewise too, the one receiving is distinguished from the one from whom he receives, but not necessarily from what he receives, for someone can receive his very self, like a liberated slave.

Exposition of the text

But if it were spoken of relatively to the Father, or posited as a relative term, it would not indicate an essence. (Sent. I, 5.1(15).2.) This appears false, because the name “God” is asserted as a relative term, and nevertheless, it indicates an essence. One should say to this that, although it indicates the essence on the side of what is being signified, still on the part of what it stands for, it indicates a person. This is why the entire explanation of the diversity in these arguments is that they do not conclude. Likewise, there is a different mode of indicating a supposit for the name “God,” as with the name “essence.”

To reveal himself, he begot that which the begetter himself is. (Sent. I, 5.1(15).5, quoting Augustine, De fide et symbolo, ch. 3, para. 4 (CSEL 41:8; PL 40:183).) On the contrary: the generation of the Son, as was said above, (Above, d. 4, q. 1, a. 3.) is not for the sake of some end—since an end is always of greater dignity than what is for the sake of the end—so it is not for the sake of manifesting the Father. To this one should say that the word “to” designates a consequence, not a final cause. For the manifestation of the Father is a consequence of the generation of the Son.

The Son is called counsel of counsel. (Sent. I, 5.1(15).7, quoting Augustine, On the Trinity, bk. 15, ch. 20 (CCSL 50A; PL 42:1087).) On the contrary: according to the Philosopher, (Aristotle, Nicomachean Ethics 3.3, 1112b24.) counsel is a certain seeking, but where there is no doubt there is no seeking, so in the divine there is no counsel. One should say to this that “counsel” can be taken passively, in reference to one who asks for or receives counsel—and this cannot be in God, since this brings in doubt. But it is also taken actively, in reference to one who gives counsel, and in this way it is in the divine, and it signifies the abundance of his knowledge about dubious things that can be done, which counsel concerns.

The Son has nothing, except his birth, (Sent. I, 5.1(15).9, quoting Hilary, On the Trinity, bk. 4, ch. 10 (CCSL 62; PL 10:103).) that is, except what he receives in being born. But he receives something in being born as what is communicated to him through the birth—that is, the essence—and something as a consequence of the birth according to the mode of understanding—that is, the relation of filiation.

And the veneration of the glory of the begotten is in honor of the begetter (Sent. I, 5.1(15).9, quoting Hilary, On the Trinity, bk. 4, ch. 10 (CCSL 62; PL 10:103).)—that is, he who honors the Son, by glorifying him as so much greater than himself, honors also the Father and vice versa: that all may honor the Son, even as they honor the Father (John 5:23).

The birth of God cannot have that nature from which it comes. (Sent. I, 5.1(15).9, quoting Hilary, On the Trinity, bk. 5, ch. 37 (CCSL 62; PL 10:155); instead of the birth, which is a literal translation, the Silano translation reads what is born.) This can be expounded in two ways: such that by “birth” we understand God himself as born, or better, we can understand it as referring to passive generation. And a passive generation is said to have the nature that is brought forth through the generation, just as every motion and change is terminated through the terminus-to-which, from which it holds its species. Therefore Hilary wishes to say that, since in every univocal generation the principle of generation and what is communicated through the generation are the same (for example, in the generation of fire the principle is the form of fire, as is what is acquired through the generation—albeit they are not the same in number), so too one begotten through the divine generation must receive the divine nature. For the divine generation occurs by virtue of the divine nature. And it must be numerically the same nature since, as has been proved, (Above, d. 4, q. 1, a. 1.) the divine nature cannot be divided in number.

We do not let the unity of the form of a servant flow back into the nature of the divine unity, (Sent. I, 5.1(15).9, quoting Hilary, On the Trinity, bk. 9, ch. 51 (CCSL 62A; PL 10:322).) that is, we do not assert that the human nature with the divine become one in nature.

Nor again do we teach that the Father is in the Son bodily, (Sent. I, 5.1(15).9, quoting Hilary, On the Trinity, bk. 9, ch. 51 (CCSL 62A; PL 10:322).) that is, when the Lord says in John 14:11, I am in the Father and the Father in me, one should not understand this such that the Father is in the Son in the way that is implied, that is, manifested, as a body is in another body. Rather, the begotten nature from the one, that is, from the Father, is of the same kind, that is, of the same power and account, just as the humanity in Socrates is of the same kind as that in Plato; that is, the very begotten one possessing such nature we say has possessed in himself the nature of the one begetting him, that is, that of the begetting Father. Or it can be expounded as about the begotten nature, since it is received in the Son through the generation, and the begetting nature, since it is the generation’s principle within the Father.

Or is it an insult to the only-begotten God to have the unbegotten God as Father? (Sent. I, 5.1(15).9, quoting Hilary, On the Trinity, bk. 9, ch. 53 (CCSL 62A; PL 10:324).) He says this against the Arians, who used to say that the Son is less than the Father because he is not unbegotten, whereas the Father is. But this does not follow, for he is the only-begotten of the Father and through that begetting he receives the entire nature of the Father. This is why he adds that he subsists in the only-begotten nature. (Sent. I, 5.1(15).9, quoting Hilary, On the Trinity, bk. 9, ch. 53 (CCSL 62A; PL 10:324).)

The one begotten does not have any other origin, (Sent. I, 5.1(15).11, quoting Hilary, On the Trinity, Bk. 5, ch. 37 (CCSL 62; PL 10:155).) that is, other than the Father. And therefore he is not referred to another, that is, to any person other than the Father, insofar as he is the Son. For he is referred to the Holy Spirit as spirating him. Or, taking it differently, any other origin might mean anything other than the Father’s essence. Likewise, it is not referred to anything else (Sent. I, 5.1(15).11, quoting Hilary, On the Trinity, bk. 5, ch. 37 (CCSL 62; PL 10:155).) can mean to the essence or nature, as one not having the divine nature but another nature. It subsists in the one, in the unity of the divine nature, from the one, that is, from the Father, or from the unity of the Father’s nature. (In the Silano translation, which does not perfectly correspond to Aquinas’s reading, the entire line being commented upon reads: it follows that whatever from the one subsists in the other is not referred to anything else.)

And so, in the begetting of the Son, the unchangeable God who begets the unchangeable God follows, if I may say so, his own nature. (Sent. I, 5.1(15).11, quoting Hilary, On the Trinity, bk. 5, ch. 37 (CCSL 62; PL 10:155).) He wishes to show how the Son is in the Father, and vice versa, in the following way. The Father, through generation, gives his own nature to the Son. Therefore, since the Father is unchangeable, he does not lose his nature, but follows it, for where his nature is, there he is. Whence, since his nature is in the Son, he is in the Son. Likewise, vice versa, the Son receives the nature that the Father has, and since the Father himself is unchangeable, he does not give up his nature; whence, since numerically the same nature given to the Son remains in the Father, the Son remains in the Father, and he is called “unchangeable” (indemutabilis) from “in” (un-) and “demutor, demutaris” (“I am changed, you are changed”).

Into the kingdom of the Son of his charity (Col 1:13). (Sent. I, 5.1(13).13. Instead of charity, Silano reads love. RSV: to the kingdom of his beloved Son.) This is expounded in two ways. For “charity” can be taken essentially, and then the meaning of, of the Son of his charity, will be “of the Son of his substance”; how one should understand this the Master will show below. (Below, perhaps 17.1(60).3‒4.) It can also be taken notionally, and then it will be an expression of emphasis, just as it is customary in Scripture that someone be called the “son of” something that most befits him; for example, Isaiah 5:1, in the horn, the son of oil, (RSV: on a very fertile hill; Aquinas follows the Vulgate.) according to its literal sense, indicates a container that one fills with oil. Also in 1 Samuel 26:16, you are a son of death, (RSV: you deserve to die; the Latin text, however, more literally captures the Hebrew.) that is, you are most worthy of death. And in the same way the only-begotten of God is called the “Son of charity” because the charity of the Father rests most of all in him.

From the foregoing words, it appears to be suggested that the divine substance begot the Son. (Sent. I, 5.1(15).17.) Here from the aforesaid authorities he draws four propositions that seem to be contrary to his own thought. One of which is that the nature is coeternal of God, wherein it seems the begotten nature is spoken of, and he explains this at but so that I may speak without prejudice and temerity, these words may be taken in this sense. (Sent. I, 5.1(15).17.) The second is that the Father begot that which he himself is, which he explains at in the same sense is also to be taken the phrase: ‘the Father generated that which he himself is.’ (Sent. I, 5.2(16).2.) The third is that the substance of God begot the Son, which he explains at also, ‘the substance of God generated the Son.’ (Sent. I, 5.2(16).3.) The fourth is that the Son is born of the substance of the Father, which he explains at similarly, ‘the Son is born from the Father’s substance.’ (Sent. I, 5.2(16).4.) And he adds a fifth, that the Son is of the substance of the Father, which he explains at expound in the same way that phrase: ‘the Son is the substance of the Father.’ (Sent. I, 5.2(16).4; the Silano translation reads, the Son of the substance. . . .)