(3) Whether mental abstraction of the relations from the persons leaves the hypostases distinct?
(4) Whether the relations, according to our mode of understanding, presuppose the acts of the persons, or contrariwise? _______________________
FIRST ARTICLE [I, Q. 40, Art. 1]
Whether Relation Is the Same As Person?
Objection 1: It would seem that in God relation is not the same as person. For when things are identical, if one is multiplied the others are multiplied. But in one person there are several relations; as in the person of the Father there is paternity and common spiration. Again, one relation exists in two person, as common spiration in the Father and in the Son. Therefore relation is not the same as person.
Obj. 2: Further, according to the Philosopher (Phys. iv, text. 24), nothing is contained by itself. But relation is in the person; nor can it be said that this occurs because they are identical, for otherwise relation would be also in the essence. Therefore relation, or property, is not the same as person in God.
Obj. 3: Further, when several things are identical, what is predicated of one is predicated of the others. But all that is predicated of a Person is not predicated of His property. For we say that the Father begets; but not that the paternity is begetting. Therefore property is not the same as person in God.
On the contrary, in God "what is" and "whereby it is" are the same, according to Boethius (De Hebdom.). But the Father is Father by paternity. In the same way, the other properties are the same as the persons.
I answer that, Different opinions have been held on this point. Some have said that the properties are not the persons, nor in the persons; and these have thought thus owing to the mode of signification of the relations, which do not indeed signify existence "in" something, but rather existence "towards" something. Whence, they styled the relations "assistant," as above explained (Q. 28, A. 2). But since relation, considered as really existing in God, is the divine essence Itself, and the essence is the same as person, as appears from what was said above (Q. 39, A. 1), relation must necessarily be the same as person.
Others, therefore, considering this identity, said that the properties were indeed the persons; but not "in" the persons; for, they said, there are no properties in God except in our way of speaking, as stated above (Q. 32, A. 2). We must, however, say that there are properties in God; as we have shown (Q. 32, A. 2). These are designated by abstract terms, being forms, as it were, of the persons. So, since the nature of a form requires it to be "in" that of which it is the form, we must say that the properties are in the persons, and yet that they are the persons; as we say that the essence is in God, and yet is God.