SCG, Book I, Chapter 33

Chapter 33: THAT NOT ALL NAMES ARE SAID OF GOD AND CREATURES IN A PURELY EQUIVOCAL WAY
[Caput Triginta Tres: Quod non omnia nomina dicuntur de Deo et creaturis pure aequivoce]

[1] … [N]ot everything predicated of God and other things is said in a purely equivocal way, in the manner of equivocals by chance [sicut ea quae sunt a casu aequivoca].

The annotated edition has it: "The theological and devotional terms which we derive from creatures and apply to God are not as the Aristotelian homonyma, where, under sameness of name, two different senses are expressed of two entirely different thing [sic], mere namesakes and nothing more, as when we call a post alike a log stuck in the ground and a delivery of letters."

[2] For in equivocals by chance [a casu aequivoca] there is no order or reference of one to another [nullus ordo aut respectus attenditur unius ad alterum], but it is entirely accidental that one name is applied to diverse things: the application of the name to one of them does not signify that it has an order to the other. But this is not the situation with names said of God and creatures, since we note in the community of such names the order of cause and effect [in huiusmodi nominum communitate ordo causae et causati]…. It is not, therefore, in the manner of pure equivocation [secundum puram aequivocationem] that something is predicated of God and other things.

[3] Furthermore, where there is pure equivocation, there is no likeness in things themselves; there is only the unity of a name. But, as is clear from what we have said, there is a certain mode of likeness of things to God [rerum autem ad Deum est aliquis modus similitudinis; cf. SCG, I, 29]. It remains, then, that names are not said of God in a purely equivocal way.

[4] Moreover, when one name is predicated of several things in a purely equivocal way, we cannot from one of them be led to the knowledge of another; for the knowledge of things does not depend on [vocal] words, but on the meaning of names [cognitio rerum non dependet ex vocibus, sed ex nominum ratione]. Now, from what we find in other things, we do arrive at a knowledge of divine things, as is evident from what we have said [cf. SCG, I, 28]. Such names, then, are not said of God and other things in a purely equivocal way.

The annotated edition seems to translate dependet ex vocibus as "by a mere coincidence of sound".

[5] Again, equivocation in a name impedes the process of reasoning [Adhuc. Aequivocatio nominis processum argumentationis impedit]. If, then, nothing was said of God and creatures except in a purely equivocal way, no reasoning proceeding from creatures to God could take place. But, the contrary is evident from [Cuius contrarium patet ex] all those who have spoken about God.

[6] … [A] name is predicated of some being uselessly unless through that name we understand something of the being [Frustra aliquod nomen de aliquo praedicatur nisi per illud nomen aliquid de eo intelligamus]. But, if names are said of God and creatures in a purely equivocal way, we understand nothing of God through those names; for the meanings of those names are known to us solely to the extent that they are said of creatures. In vain, therefore, would it be said or proved of God that He is a being, good, or the like.

[7] Should it be replied that through such names we know only what God is not, namely, that God is called living because He does not belong to the genus of lifeless things, and so with the other names, it will at least have to be the case that living said of God and creatures agrees in the denial of the lifeless. Thus, it will not be said in a purely equivocal way.

As the annotated edition remarks, "St Thomas says what suffices for his present argument: he is not undertaking to exhaust the sense of the phrase 'living God.'" The upshot of this chapter is that we do have some positive knowledge of God by the very act of articulating the (apophatic) limits thereof.