Summa Th. I EN Qu.37 a.2
Objection: 1. It would seem that the Father and the Son do not love each other by the Holy Ghost. For Augustine (De Trin. vii, 1) proves that the Father is not wise by the Wisdom begotten. But as the Son is Wisdom begotten, so the Holy Ghost is the Love proceeding, as explained above (Question [27], Article [3]). Therefore the Father and the Son do not love Themselves by the Love proceeding, which is the Holy Ghost.
2. Further, the proposition, "The Father and the Son love each other by the Holy Ghost," this word "love" is to be taken either essentially or notionally. But it cannot be true if taken essentially, because in the same way we might say that "the Father understands by the Son"; nor, again, if it is taken notionally, for then, in like manner, it might be said that "the Father and the Son spirate by the Holy Ghost," or that "the Father generates by the Son." Therefore in no way is this proposition true: "'The Father and the Son love each other by the Holy Ghost."
3. Further, by the same love the Father loves the Son, and Himself, and us. But the Father does not love Himself by the Holy Ghost; for no notional act is reflected back on the principle of the act; since it cannot be said that the "Father begets Himself," or that "He spirates Himself." Therefore, neither can it be said that "He loves Himself by the Holy Ghost," if "to love" is taken in a notional sense. Again, the love wherewith He loves us is not the Holy Ghost; because it imports a relation to creatures, and this belongs to the essence. Therefore this also is false: "The Father loves the Son by the Holy Ghost."
On the contrary Augustine says (De Trin. vi, 5): "The Holy Ghost is He whereby the Begotten is loved by the one begetting and loves His Begetter."
I answer that A difficulty about this question is objected to the effect that when we say, "the Father loves the Son by the Holy Ghost," since the ablative is construed as denoting a cause, it seems to mean that the Holy Ghost is the principle of love to the Father and the Son; which cannot be admitted.
In view of this difficulty some have held that it is false, that "the Father and the Son love each other by the Holy Ghost"; and they add that it was retracted by Augustine when he retracted its equivalent to the effect that "the Father is wise by the Wisdom begotten." Others say that the proposition is inaccurate and ought to be expounded, as that "the Father loves the Son by the Holy Ghost"---that is, "by His essential Love," which is appropriated to the Holy Ghost. Others further say that this ablative should be construed as importing a sign, so that it means, "the Holy Ghost is the sign that the Father loves the Son"; inasmuch as the Holy Ghost proceeds from them both, as Love. Others, again, say that this ablative must be construed as importing the relation of formal cause, because the Holy Ghost is the love whereby the Father and the Son formally love each other. Others, again, say that it should be construed as importing the relation of a formal effect; and these approach nearer to the truth.
To make the matter clear, we must consider that since a thing is commonly denominated from its forms, as "white" from whiteness, and "man" from humanity; everything whence anything is denominated, in this particular respect stands to that thing in the relation of form. So when I say, "this man is clothed with a garment," the ablative is to be construed as having relation to the formal cause, although the garment is not the form. Now it may happen that a thing may be denominated from that which proceeds from it, not only as an agent is from its action, but also as from the term itself of the action---that is, the effect, when the effect itself is included in the idea of the action. For we say that fire warms by heating, although heating is not the heat which is the form of the fire, but is an action proceeding from the fire; and we say that a tree flowers with the flower, although the flower is not the tree's form, but is the effect proceeding from the form. In this way, therefore, we must say that since in God "to love" is taken in two ways, essentially and notionally, when it is taken essentially, it means that the Father and the Son love each other not by the Holy Ghost, but by their essence. Hence Augustine says (De Trin. xv, 7): "Who dares to say that the Father loves neither Himself, nor the Son, nor the Holy Ghost, except by the Holy Ghost?" The opinions first quoted are to be taken in this sense. But when the term Love is taken in a notional sense it means nothing else than "to spirate love"; just as to speak is to produce a word, and to flower is to produce flowers. As therefore we say that a tree flowers by its flower, so do we say that the Father, by the Word or the Son, speaks Himself, and His creatures; and that the Father and the Son love each other and us, by the Holy Ghost, or by Love proceeding.
Reply to Objection: 1. To be wise or intelligent is taken only essentially in God; therefore we cannot say that "the Father is wise or intelligent by the Son." But to love is taken not only essentially, but also in a notional sense; and in this way, we can say that the Father and the Son love each other by the Holy Ghost, as was above explained.
2. When the idea of an action includes a determined effect, the principle of the action may be denominated both from the action, and from the effect; so we can say, for instance, that a tree flowers by its flowering and by its flower. When, however, the idea of an action does not include a determined effect, then in that case, the principle of the action cannot be denominated from the effect, but only from the action. For we do not say that the tree produces the flower by the flower, but by the production of the flower. So when we say, "spirates" or "begets," this imports only a notional act. Hence we cannot say that the Father spirates by the Holy Ghost, or begets by the Son. But we can say that the Father speaks by the Word, as by the Person proceeding, "and speaks by the speaking," as by a notional act; forasmuch as "to speak" imports a determinate person proceeding; since "to speak" means to produce a word. Likewise to love, taken in a notional sense, means to produce love; and so it can be said that the Father loves the Son by the Holy Ghost, as by the person proceeding, and by Love itself as a notional act.
3. The Father loves not only the Son, but also Himself and us, by the Holy Ghost; because, as above explained, to love, taken in a notional sense, not only imports the production of a divine person, but also the person produced, by way of love, which has relation to the object loved. Hence, as the Father speaks Himself and every creature by His begotten Word, inasmuch as the Word "begotten" adequately represents the Father and every creature; so He loves Himself and every creature by the Holy Ghost, inasmuch as the Holy Ghost proceeds as the love of the primal goodness whereby the Father loves Himself and every creature. Thus it is evident that relation to the creature is implied both in the Word and in the proceeding Love, as it were in a secondary way, inasmuch as the divine truth and goodness are a principle of understanding and loving all creatures.
There now follows the consideration of the Gift; concerning which there are two points of inquiry:
(1) Whether "Gift" can be a personal name?
(2) Whether it is the proper name of the Holy Ghost?
Objection: 1. It would seem that "Gift" is not a personal name. For every personal name imports a distinction in God. But the name of "Gift" does not import a distinction in God; for Augustine says (De Trin. xv, 19): that "the Holy Ghost is so given as God's Gift, that He also gives Himself as God." Therefore "Gift" is not a personal name.
2. Further, no personal name belongs to the divine essence. But the divine essence is the Gift which the Father gives to the Son, as Hilary says (De Trin. ix). Therefore "Gift" is not a personal name.
3. Further, according to Damascene (De Fide Orth. iv, 19) there is no subjection nor service in the divine persons. But gift implies a subjection both as regards him to whom it is given, and as regards him by whom it is given. Therefore "Gift" is not a personal name.
4. Further, "Gift" imports relation to the creature, and it thus seems to be said of God in time. But personal names are said of God from eternity; as "Father," and "Son." Therefore "Gift" is not a personal name.
On the contrary Augustine says (De Trin. xv, 19): "As the body of flesh is nothing but flesh; so the gift of the Holy Ghost is nothing but the Holy Ghost." But the Holy Ghost is a personal name; so also therefore is "Gift."
I answer that The word "gift" imports an aptitude for being given. And what is given has an aptitude or relation both to the giver and to that to which it is given. For it would not be given by anyone, unless it was his to give; and it is given to someone to be his. Now a divine person is said to belong to another, either by origin, as the Son belongs to the Father; or as possessed by another. But we are said to possess what we can freely use or enjoy as we please: and in this way a divine person cannot be possessed, except by a rational creature united to God. Other creatures can be moved by a divine person, not, however, in such a way as to be able to enjoy the divine person, and to use the effect thereof. The rational creature does sometimes attain thereto; as when it is made partaker of the divine Word and of the Love proceeding, so as freely to know God truly and to love God rightly. Hence the rational creature alone can possess the divine person. Nevertheless in order that it may possess Him in this manner, its own power avails nothing: hence this must be given it from above; for that is said to be given to us which we have from another source. Thus a divine person can "be given," and can be a "gift."
Reply to Objection: 1. The name "Gift" imports a personal distinction , in so far as gift imports something belonging to another through its origin. Nevertheless, the Holy Ghost gives Himself, inasmuch as He is His own, and can use or rather enjoy Himself; as also a free man belongs to himself. And as Augustine says (In Joan. Tract. xxix): "What is more yours than yourself?" Or we might say, and more fittingly, that a gift must belong in a way to the giver. But the phrase, "this is this one's," can be understood in several senses. In one way it means identity, as Augustine says (In Joan. Tract. xxix); and in that sense "gift" is the same as "the giver," but not the same as the one to whom it is given. The Holy Ghost gives Himself in that sense. In another sense, a thing is another's as a possession, or as a slave; and in that sense gift is essentially distinct from the giver; and the gift of God so taken is a created thing. In a third sense "this is this one's" through its origin only; and in this sense the Son is the Father's; and the Holy Ghost belongs to both. Therefore, so far as gift in this way signifies the possession of the giver, it is personally distinguished from the giver, and is a personal name.
2. The divine essence is the Father's gift in the first sense, as being the Father's by way of identity.
3. Gift as a personal name in God does not imply subjection, but only origin, as regards the giver; but as regards the one to whom it is given, it implies a free use, or enjoyment, as above explained.
4. Gift is not so called from being actually given, but from its aptitude to be given. Hence the divine person is called Gift from eternity, although He is given in time. Nor does it follow that it is an essential name because it imports relation to the creature; but that it includes something essential in its meaning; as the essence is included in the idea of person, as stated above (Question [34], Article [3]).
Objection: 1. It would seem that Gift is not the proper name of the Holy Ghost. For the name Gift comes from being given. But, as Is 9,16 says: "A Son is give to us." Therefore to be Gift belongs to the Son, as well as to the Holy Ghost.
2. Further, every proper name of a person signifies a property. But this word Gift does not signify a property of the Holy Ghost. Therefore Gift is not a proper name of the Holy Ghost.
3. Further, the Holy Ghost can be called the spirit of a man, whereas He cannot be called the gift of any man, but "God's Gift" only. Therefore Gift is not the proper name of the Holy Ghost.
On the contrary Augustine says (De Trin. iv, 20): "As 'to be born' is, for the Son, to be from the Father, so, for the Holy Ghost, 'to be the Gift of God' is to proceed from Father and Son." But the Holy Ghost receives His proper name from the fact that He proceeds from Father and Son. Therefore Gift is the proper name of the Holy Ghost.
I answer that Gift, taken personally in God, is the proper name of the Holy Ghost.
In proof of this we must know that a gift is properly an unreturnable giving, as Aristotle says (Topic. iv, 4)---i.e. a thing which is not given with the intention of a return---and it thus contains the idea of a gratuitous donation. Now, the reason of donation being gratuitous is love; since therefore do we give something to anyone gratuitously forasmuch as we wish him well. So what we first give him is the love whereby we wish him well. Hence it is manifest that love has the nature of a first gift, through which all free gifts are given. So since the Holy Ghost proceeds as love, as stated above (Question [27], Article [4]; Question [37], Article [1]), He proceeds as the first gift. Hence Augustine says (De Trin. xv, 24): "By the gift, which is the Holy Ghost, many particular gifts are portioned out to the members of Christ."
Reply to Objection: 1. As the Son is properly called the Image because He proceeds by way of a word, whose nature it is to be the similitude of its principle, although the Holy Ghost also is like to the Father; so also, because the Holy Ghost proceeds from the Father as love, He is properly called Gift, although the Son, too, is given. For that the Son is given is from the Father's love, according to the words, "God so loved the world, as to give His only begotten Son" (Jn 3,16).
2. The name Gift involves the idea of belonging to the Giver through its origin; and thus it imports the property of the origin of the Holy Ghost---that is, His procession.
3. Before a gift is given, it belongs only to the giver; but when it is given, it is his to whom it is given. Therefore, because "Gift" does not import the actual giving, it cannot be called a gift of man, but the Gift of God giving. When, however, it has been given, then it is the spirit of man, or a gift bestowed on man.
Those things considered which belong to the divine persons absolutely, we next treat of what concerns the person in reference to the essence, to the properties, and to the notional acts; and of the comparison of these with each other.
As regards the first of these, there are eight points of inquiry:
(1) Whether the essence in God is the same as the person?
(2) Whether we should say that the three persons are of one essence?
(3) Whether essential names should be predicated of the persons in the plural, or in the singular?
(4) Whether notional adjectives, or verbs, or participles, can be predicated of the essential names taken in a concrete sense?
(5) Whether the same can be predicated of essential names taken in the abstract?
(6) Whether the names of the persons can be predicated of concrete essential names?
(7) Whether essential attributes can be appropriated to the persons?
(8) Which attributes should be appropriated to each person?
Objection: 1. It would seem that in God the essence is not the same as person. For whenever essence is the same as person or "suppositum," there can be only one "suppositum" of one nature, as is clear in the case of all separate substances. For in those things which are really one and the same, one cannot be multiplied apart from the other. But in God there is one essence and three persons, as is clear from what is above expounded (Question [28], Article [3]; Question [30], Article [2]). Therefore essence is not the same as person.
2. Further, simultaneous affirmation and negation of the same things in the same respect cannot be true. But affirmation and negation are true of essence and of person. For person is distinct, whereas essence is not. Therefore person and essence are not the same.
3. Further, nothing can be subject to itself. But person is subject to essence; whence it is called "suppositum" or "hypostasis." Therefore person is not the same as essence.
On the contrary Augustine says (De Trin. vi, 7): "When we say the person of the Father we mean nothing else but the substance of the Father."
I answer that The truth of this question is quite clear if we consider the divine simplicity. For it was shown above (Question [3], Article [3]) that the divine simplicity requires that in God essence is the same as "suppositum," which in intellectual substances is nothing else than person. But a difficulty seems to arise from the fact that while the divine persons are multiplied, the essence nevertheless retains its unity. And because, as Boethius says (De Trin. i), "relation multiplies the Trinity of persons," some have thought that in God essence and person differ, forasmuch as they held the relations to be "adjacent"; considering only in the relations the idea of "reference to another," and not the relations as realities. But as it was shown above (Question [28], Article [2]) in creatures relations are accidental, whereas in God they are the divine essence itself. Thence it follows that in God essence is not really distinct from person; and yet that the persons are really distinguished from each other. For person, as above stated (Question [29], Article [4]), signifies relation as subsisting in the divine nature. But relation as referred to the essence does not differ therefrom really, but only in our way of thinking; while as referred to an opposite relation, it has a real distinction by virtue of that opposition. Thus there are one essence and three persons.
Reply to Objection: 1. There cannot be a distinction of "suppositum" in creatures by means of relations, but only by essential principles; because in creatures relations are not subsistent. But in God relations are subsistent, and so by reason of the opposition between them they distinguish the "supposita"; and yet the essence is not distinguished, because the relations themselves are not distinguished from each other so far as they are identified with the essence.
2. As essence and person in God differ in our way of thinking, it follows that something can be denied of the one and affirmed of the other; and therefore, when we suppose the one, we need not suppose the other.
3. Divine things are named by us after the way of created things, as above explained (Question [13], Articles [1],3). And since created natures are individualized by matter which is the subject of the specific nature, it follows that individuals are called "subjects," "supposita," or "hypostases." So the divine persons are named "supposita" or "hypostases," but not as if there really existed any real "supposition" or "subjection."
Objection: 1. It would seem not right to say that the three persons are of one essence. For Hilary says (De Synod.) that the Father, Son and Holy Ghost "are indeed three by substance, but one in harmony." But the substance of God is His essence. Therefore the three persons are not of one essence.
2. Further, nothing is to be affirmed of God except what can be confirmed by the authority of Holy Writ, as appears from Dionysius (Div. Nom. i). Now Holy Writ never says that the Father, Son and Holy Ghost are of one essence. Therefore this should not be asserted.
3. Further, the divine nature is the same as the divine essence. It suffices therefore to say that the three persons are of one nature.
4. Further, it is not usual to say that the person is of the essence; but rather that the essence is of the person. Therefore it does not seem fitting to say that the three persons are of one essence.
5. Further, Augustine says (De Trin. vii, 6) that we do not say that the three persons are "from one essence [ex una essentia]," lest we should seem to indicate a distinction between the essence and the persons in God. But prepositions which imply transition, denote the oblique case. Therefore it is equally wrong to say that the three persons are "of one essence [unius essentiae]."
6. Further, nothing should be said of God which can be occasion of error. Now, to say that the three persons are of one essence or substance, furnishes occasion of error. For, as Hilary says (De Synod.): "One substance predicated of the Father and the Son signifies either one subsistent, with two denominations; or one substance divided into two imperfect substances; or a third prior substance taken and assumed by the other two." Therefore it must not be said that the three persons are of one substance.
On the contrary Augustine says (Contra Maxim. iii) that the word (homoousion), which the Council of Nicaea adopted against the Arians, means that the three persons are of one essence.
I answer that As above explained (Question [13], Articles [1],2), divine things are named by our intellect, not as they really are in themselves, for in that way it knows them not; but in a way that belongs to things created. And as in the objects of the senses, whence the intellect derives its knowledge, the nature of the species is made individual by the matter, and thus the nature is as the form, and the individual is the "suppositum" of the form; so also in God the essence is taken as the form of the three persons, according to our mode of signification. Now in creatures we say that every form belongs to that whereof it is the form; as the health and beauty of a man belongs to the man. But we do not say of that which has a form, that it belongs to the form, unless some adjective qualifies the form; as when we say: "That woman is of a handsome figure," or: "This man is of perfect virtue." In like manner, as in God the persons are multiplied, and the essence is not multiplied, we speak of one essence of the three persons, and three persons of the one essence, provided that these genitives be understood as designating the form.
Reply to Objection: 1. Substance is here taken for the "hypostasis," and not for the essence.
2. Although we may not find it declared in Holy Writ in so many words that the three persons are of one essence, nevertheless we find it so stated as regards the meaning; for instance, "I and the Father are one (Jn 10,30)," and "I am in the Father, and the Father in Me (Jn 10,38)"; and there are many other texts of the same import.
3. Because "nature" designates the principle of action while "essence" comes from being [essendo], things may be said to be of one nature which agree in some action, as all things which give heat; but only those things can be said to be of "one essence" which have one being. So the divine unity is better described by saying that the three persons are "of one essence," than by saying they are "of one nature."
4. Form, in the absolute sense, is wont to be designated as belonging to that of which it is the form, as we say "the virtue of Peter." On the other hand, the thing having form is not wont to be designated as belonging to the form except when we wish to qualify or designate the form. In which case two genitives are required, one signifying the form, and the other signifying the determination of the form, as, for instance, when we say, "Peter is of great virtue [magnae virtutis]," or else one genitive must have the force of two, as, for instance, "he is a man of blood"---that is, he is a man who sheds much blood [multi sanguinis]. So, because the divine essence signifies a form as regards the person, it may properly be said that the essence is of the person; but we cannot say the converse, unless we add some term to designate the essence; as, for instance, the Father is a person of the "divine essence"; or, the three persons are "of one essence."
5. The preposition "from" or "out of" does not designate the habitude of a formal cause, but rather the habitude of an efficient or material cause; which causes are in all cases distinguished from those things of which they are the causes. For nothing can be its own matter, nor its own active principle. Yet a thing may be its own form, as appears in all immaterial things. So, when we say, "three persons of one essence," taking essence as having the habitude of form, we do not mean that essence is different from person, which we should mean if we said, "three persons from the same essence."
6. As Hilary says (De Synod.): "It would be prejudicial to holy things, if we had to do away with them, just because some do not think them holy. So if some misunderstand (homoousion), what is that to me, if I understand it rightly? . . . The oneness of nature does not result from division, or from union or from community of possession, but from one nature being proper to both Father and Son."
Objection: 1. It would seem that essential names, as the name "God," should not be predicated in the singular of the three persons, but in the plural. For as "man" signifies "one that has humanity," so God signifies "one that has Godhead." But the three persons are three who have Godhead. Therefore the three persons are "three Gods."
2. Further, Gn 1,1, where it is said, "In the beginning God created heaven and earth," the Hebrew original has "Elohim," which may be rendered "Gods" or "Judges": and this word is used on account of the plurality of persons. Therefore the three persons are "several Gods," and not "one" God.
3. Further, this word "thing" when it is said absolutely, seems to belong to substance. But it is predicated of the three persons in the plural. For Augustine says (De Doctr. Christ. i, 5): "The things that are the objects of our future glory are the Father, Son and Holy Ghost." Therefore other essential names can be predicated in the plural of the three persons.
4. Further, as this word "God" signifies "a being who has Deity," so also this word "person" signifies a being subsisting in an intellectual nature. But we say there are three persons. So for the same reason we can say there are "three Gods."
On the contrary It is said (Dt 6,4): "Hear, O Israel, the Lord thy God is one God."
I answer that Some essential names signify the essence after the manner of substantives; while others signify it after the manner of adjectives. Those which signify it as substantives are predicated of the three persons in the singular only, and not in the plural. Those which signify the essence as adjectives are predicated of the three persons in the plural. The reason of this is that substantives signify something by way of substance, while adjectives signify something by way of accident, which adheres to a subject. Now just as substance has existence of itself, so also it has of itself unity or multitude; wherefore the singularity or plurality of a substantive name depends upon the form signified by the name. But as accidents have their existence in a subject, so they have unity or plurality from their subject; and therefore the singularity and plurality of adjectives depends upon their "supposita." In creatures, one form does not exist in several "supposita" except by unity of order, as the form of an ordered multitude. So if the names signifying such a form are substantives, they are predicated of many in the singular, but otherwise if they adjectives. For we say that many men are a college, or an army, or a people; but we say that many men are collegians. Now in God the divine essence is signified by way of a form, as above explained (Article [2]), which, indeed, is simple and supremely one, as shown above (Question [3], Article [7]; Question [11], Article [4]). So, names which signify the divine essence in a substantive manner are predicated of the three persons in the singular, and not in the plural. This, then, is the reason why we say that Socrates, Plato and Cicero are "three men"; whereas we do not say the Father, Son and Holy Ghost are "three Gods," but "one God"; forasmuch as in the three "supposita" of human nature there are three humanities, whereas in the three divine Persons there is but one divine essence. On the other hand, the names which signify essence in an adjectival manner are predicated of the three persons plurally, by reason of the plurality of "supposita." For we say there are three "existent" or three "wise" beings, or three "eternal," "uncreated," and "immense" beings, if these terms are understood in an adjectival sense. But if taken in a substantive sense, we say "one uncreated, immense, eternal being," as Athanasius declares.
Reply to Objection: 1. Though the name "God" signifies a being having Godhead, nevertheless the mode of signification is different. For the name "God" is used substantively; whereas "having Godhead" is used adjectively. Consequently, although there are "three having Godhead," it does not follow that there are three Gods.
2. Various languages have diverse modes of expression. So as by reason of the plurality of "supposita" the Greeks said "three hypostases," so also in Hebrew "Elohim" is in the plural. We, however, do not apply the plural either to "God" or to "substance," lest plurality be referred to the substance.
3. This word "thing" is one of the transcendentals. Whence, so far as it is referred to relation, it is predicated of God in the plural; whereas, so far as it is referred to the substance, it is predicated in the singular. So Augustine says, in the passage quoted, that "the same Trinity is a thing supreme."
4. The form signified by the word "person" is not essence or nature, but personality. So, as there are three personalities---that is, three personal properties in the Father, Son and Holy Ghost---it is predicated of the three, not in the singular, but in the plural.
Objection: 1. It would seem that the concrete, essential names cannot stand for the person, so that we can truly say "God begot God." For, as the logicians say, "a singular term signifies what it stands for." But this name "God" seems to be a singular term, for it cannot be predicated in the plural, as above explained (Article [3]). Therefore, since it signifies the essence, it stands for essence, and not for person.
2. Further, a term in the subject is not modified by a term in the predicate, as to its signification; but only as to the sense signified in the predicate. But when I say, "God creates," this name "God" stands for the essence. So when we say "God begot," this term "God" cannot by reason of the notional predicate, stand for person.
3. Further, if this be true, "God begot," because the Father generates; for the same reason this is true, "God does not beget," because the Son does not beget. Therefore there is God who begets, and there is God who does not beget; and thus it follows that there are two Gods.
4. Further, if "God begot God," He begot either God, that is Himself, or another God. But He did not beget God, that is Himself; for, as Augustine says (De Trin. i, 1), "nothing begets itself." Neither did He beget another God; as there is only one God. Therefore it is false to say, "God begot God."
5. Further, if "God begot God," He begot either God who is the Father, or God who is not the Father. If God who is the Father, then God the Father was begotten. If God who is not the Father, then there is a God who is not God the Father: which is false. Therefore it cannot be said that "God begot God."
On the contrary In the Creed it is said, "God of God."
I answer that Some have said that this name "God" and the like, properly according to their nature, stand for the essence, but by reason of some notional adjunct are made to stand for the Person. This opinion apparently arose from considering the divine simplicity, which requires that in God, He "who possesses" and "what is possessed" be the same. So He who possesses Godhead, which is signified by the name God, is the same as Godhead. But when we consider the proper way of expressing ourselves, the mode of signification must be considered no less than the thing signified. Hence as this word "God" signifies the divine essence as in Him Who possesses it, just as the name "man" signifies humanity in a subject, others more truly have said that this word "God," from its mode of signification, can, in its proper sense, stand for person, as does the word "man." So this word "God" sometimes stands for the essence, as when we say "God creates"; because this predicate is attributed to the subject by reason of the form signified---that is, Godhead. But sometimes it stands for the person, either for only one, as when we say, "God begets," or for two, as when we say, "God spirates"; or for three, as when it is said: "To the King of ages, immortal, invisible, the only God," etc. (1Tm 1,17).
Reply to Objection: 1. Although this name "God" agrees with singular terms as regards the form signified not being multiplied; nevertheless it agrees also with general terms so far as the form signified is to be found in several "supposita." So it need not always stand for the essence it signifies.
2. This holds good against those who say that the word "God" does not naturally stand for person.
3. The word "God" stands for the person in a different way from that in which this word "man" does; for since the form signified by this word "man"---that is, humanity---is really divided among its different subjects, it stands of itself for the person, even if there is no adjunct determining it to the person---that is, to a distinct subject. The unity or community of the human nature, however, is not a reality, but is only in the consideration of the mind. Hence this term "man" does not stand for the common nature, unless this is required by some adjunct, as when we say, "man is a species"; whereas the form signified by the name "God"---that is, the divine essence---is really one and common. So of itself it stands for the common nature, but by some adjunct it may be restricted so as to stand for the person. So, when we say, "God generates," by reason of the notional act this name "God" stands for the person of the Father. But when we say, "God does not generate," there is no adjunct to determine this name to the person of the Son, and hence the phrase means that generation is repugnant to the divine nature. If, however, something be added belonging to the person of the Son, this proposition, for instance, "God begotten does not beget," is true. Consequently, it does not follow that there exists a "God generator," and a "God not generator"; unless there be an adjunct pertaining to the persons; as, for instance, if we were to say, "the Father is God the generator" and the "Son is God the non-generator" and so it does not follow that there are many Gods; for the Father and the Son are one God, as was said above (Article [3]).
4. This is false, "the Father begot God, that is Himself," because the word "Himself," as a reciprocal term, refers to the same "suppositum." Nor is this contrary to what Augustine says (Ep. lxvi ad Maxim.) that "God the Father begot another self [alterum se]," forasmuch as the word "se" is either in the ablative case, and then it means "He begot another from Himself," or it indicates a single relation, and thus points to identity of nature. This is, however, either a figurative or an emphatic way of speaking, so that it would really mean, "He begot another most like to Himself." Likewise also it is false to say, "He begot another God," because although the Son is another than the Father, as above explained (Question [31], Article [2]), nevertheless it cannot be said that He is "another God"; forasmuch as this adjective "another" would be understood to apply to the substantive God; and thus the meaning would be that there is a distinction of Godhead. Yet this proposition "He begot another God" is tolerated by some, provided that "another" be taken as a substantive, and the word "God" be construed in apposition with it. This, however, is an inexact way of speaking, and to be avoided, for fear of giving occasion to error.
5. To say, "God begot God Who is God the Father," is wrong, because since the word "Father" is construed in apposition to "God," the word "God" is restricted to the person of the Father; so that it would mean, "He begot God, Who is Himself the Father"; and then the Father would be spoken of as begotten, which is false. Wherefore the negative of the proposition is true, "He begot God Who is not God the Father." If however, we understand these words not to be in apposition, and require something to be added, then, on the contrary, the affirmative proposition is true, and the negative is false; so that the meaning would be, "He begot God Who is God Who is the Father." Such a rendering however appears to be forced, so that it is better to say simply that the affirmative proposition is false, and the negative is true. Yet Prepositivus said that both the negative and affirmative are false, because this relative "Who" in the affirmative proposition can be referred to the "suppositum"; whereas in the negative it denotes both the thing signified and the "suppositum." Whence, in the affirmative the sense is that "to be God the Father" is befitting to the person of the Son; and in the negative sense is that "to be God the Father," is to be removed from the Son's divinity as well as from His personality. This, however, appears to be irrational; since, according to the Philosopher (Peri Herm. ii), what is open to affirmation, is open also to negation.
Summa Th. I EN Qu.37 a.2