Reply Obj. 1: The Arians, who sprang from Origen, declared that the Son differed in substance from the Father. Hence, they endeavored to maintain that when the Son of God is called the Word, this is not to be understood in a strict sense; lest the idea of the Word proceeding should compel them to confess that the Son of God is of the same substance as the Father. For the interior word proceeds in such a manner from the one who pronounces it, as to remain within him. But supposing Word to be said metaphorically of God, we must still admit Word in its strict sense. For if a thing be called a word metaphorically, this can only be by reason of some manifestation; either it makes something manifest as a word, or it is manifested by a word. If manifested by a word, there must exist a word whereby it is manifested. If it is called a word because it exteriorly manifests, what it exteriorly manifests cannot be called word except in as far as it signifies the interior concept of the mind, which anyone may also manifest by exterior signs. Therefore, although Word may be sometimes said of God metaphorically, nevertheless we must also admit Word in the proper sense, and which is said personally.
Reply Obj. 2: Nothing belonging to the intellect can be applied to God personally, except word alone; for word alone signifies that which emanates from another. For what the intellect forms in its conception is the word. Now, the intellect itself, according as it is made actual by the intelligible species, is considered absolutely; likewise the act of understanding which is to the actual intellect what existence is to actual being; since the act of understanding does not signify an act going out from the intelligent agent, but an act remaining in the agent. Therefore when we say that word is knowledge, the term knowledge does not mean the act of a knowing intellect, or any one of its habits, but stands for what the intellect conceives by knowing. Hence also Augustine says (De Trin. vii, 1) that the Word is "begotten wisdom;" for it is nothing but the concept of the Wise One; and in the same way It can be called "begotten knowledge." Thus can also be explained how "to speak" is in God "to see by thought," forasmuch as the Word is conceived by the gaze of the divine thought. Still the term "thought" does not properly apply to the Word of God. For Augustine says (De Trin. xv, 16): "Therefore do we speak of the Word of God, and not of the Thought of God, lest we believe that in God there is something unstable, now assuming the form of Word, now putting off that form and remaining latent and as it were formless." For thought consists properly in the search after the truth, and this has no place in God. But when the intellect attains to the form of truth, it does not think, but perfectly contemplates the truth. Hence Anselm (Monol. lx) takes "thought" in an improper sense for "contemplation."
Reply Obj. 3: As, properly speaking, Word in God is said personally, and not essentially, so likewise is to "speak." Hence, as the Word is not common to the Father, Son and Holy Ghost, so it is not true that the Father, Son, and Holy Ghost are one speaker. So Augustine says (De Trin. vii, 1): "He who speaks in that co-eternal Word is understood as not alone in God, but as being with that very Word, without which, forsooth, He would not be speaking." On the other hand, "to be spoken" belongs to each Person, for not only is the word spoken, but also the thing understood or signified by the word. Therefore in this manner to one person alone in God does it belong to be spoken in the same way as a word is spoken; whereas in the way whereby a thing is spoken as being understood in the word, it belongs to each Person to be spoken. For the Father, by understanding Himself, the Son and the Holy Ghost, and all other things comprised in this knowledge, conceives the Word; so that thus the whole Trinity is "spoken" in the Word; and likewise also all creatures: as the intellect of a man by the word he conceives in the act of understanding a stone, speaks a stone. Anselm took the term "speak" improperly for the act of understanding; whereas they really differ from each other; for "to understand" means only the habitude of the intelligent agent to the thing understood, in which habitude no trace of origin is conveyed, but only a certain information of our intellect; forasmuch as our intellect is made actual by the form of the thing understood. In God, however, it means complete identity, because in God the intellect and the thing understood are altogether the same, as was proved above (Q. 14, AA. 4, 5). Whereas to "speak" means chiefly the habitude to the word conceived; for "to speak" is nothing but to utter a word. But by means of the word it imports a habitude to the thing understood which in the word uttered is manifested to the one who understands. Thus, only the Person who utters the Word is "speaker" in God, although each Person understands and is understood, and consequently is spoken by the Word.
Reply Obj. 4: The term "word" is there taken figuratively, as the thing signified or effected by word is called word. For thus creatures are said to do the word of God, as executing any effect, whereto they are ordained from the word conceived of the divine wisdom; as anyone is said to do the word of the king when he does the work to which he is appointed by the king's word. _______________________
SECOND ARTICLE [I, Q. 34, Art. 2]
Whether "Word" Is the Son's Proper Name?
Objection 1: It would seem that "Word" is not the proper name of the Son. For the Son is a subsisting person in God. But word does not signify a subsisting thing, as appears in ourselves. Therefore word cannot be the proper name of the person of the Son.
Obj. 2: Further, the word proceeds from the speaker by being uttered.
Therefore if the Son is properly the word, He proceeds from the
Father, by way only of utterance; which is the heresy of Valentine;
as appears from Augustine (De Haeres. xi).
Obj. 3: Further, every proper name of a person signifies some property of that person. Therefore, if the Word is the Son's proper name, it signifies some property of His; and thus there will be several more properties in God than those above mentioned.
Obj. 4: Further, whoever understands conceives a word in the act of understanding. But the Son understands. Therefore some word belongs to the Son; and consequently to be Word is not proper to the Son.