On the Holy Trinity

^8. Further, in regard to that very generic (generalis) word, if on this account we say three persons, because that which person means is common to them (otherwise they can in no way be so called, just as they are not called three sons, because that which son means is not common to them); why do we not also say three Gods? For certainly, since the Father is a person, and the Son a person, and the Holy Spirit a person, therefore there are three persons: since then the Father is God, and the Son God, and the Holy Spirit God, why not three Gods? Or else, since on account of their ineffable union these three are together one God, why not also one person; so that we could not say three persons, although we call each a person singly, just as we cannot say three Gods, although we call each singly God, whether the Father, or the Son, or the Holy Spirit? Is it because Scripture does not say three Gods? But neither do we find that Scripture anywhere mentions three persons. Or is it because Scripture does not call these three, either three persons or one person (for we read of the person of the Lord, but not of the Lord as a person), that therefore it was lawful through the mere necessity of speaking and reasoning to say three persons, not because Scripture says it, but because Scripture does not contradict it: whereas, if we were to say three Gods, Scripture would contradict it, which says, “Hear, O Israel; the Lord your God is one God?” Why then is it not also lawful to say three essences; which, in like manner, as Scripture does not say, so neither does it contradict? For if essence is a specific (specialis) name common to three, why are They not to be called three essences, as Abraham, Isaac, and Jacob are called three men, because man is the specific name common to all men? But if essence is not a specific name, but a generic one, since man, and cattle, and tree, and constellation, and angel, are called essences; why are not these called three essences, as three horses are called three animals, and three laurels are called three trees, and three stones three bodies? Or if they are not called three essences, but one essence, on account of the unity of the Trinity, why is it not the case, that on account of the same unity of the Trinity they are not to be called three substances or three persons, but one substance and one person? For as the name of essence is common to them, so that each singly is called essence, so the name of either substance or person is common to them. For that which must be understood of persons according to our usage, this is to be understood of substances according to the Greek usage; for they say three substances, one essence, in the same way as we say three persons, one essence or substance.

9. What therefore remains, except that we confess that these terms sprang from the necessity of speaking, when copious reasoning was required against the devices or errors of the heretics? For when human weakness endeavored to utter in speech to the senses of man what it grasps in the secret places of the mind in proportion to its comprehension respecting the Lord God its creator, whether by devout faith, or by any discernment whatsoever; it feared to say three essences, lest any difference should be understood to exist in that absolute equality. Again, it could not say that there were not three somewhats (tria quædam), for it was because Sabellius said this that he fell into heresy. For it must be devoutly believed, as most certainly known from the Scriptures, and must be grasped by the mental eye with undoubting perception, that there is both Father, and Son, and Holy Spirit; and that the Son is not the same with the Father, nor the Holy Spirit the same with the Father or the Son. It sought then what three it should call them, and answered substances or persons; by which names it did not intend diversity to be meant, but singleness to be denied: that not only unity might be understood therein from the being called one essence, but also Trinity from the being called three substances or persons. For if it is the same thing with God to be (esse) as to subsist (subsistere), they were not to be called three substances, in such sense as they are not called three essences; just as, because it is the same thing with God to be as to be wise, as we do not say three essences, so neither three wisdoms. For so, because it is the same thing to Him to be God as to be, it is not right to say three essences, as it is not right to say three Gods. But if it is one thing to God to be, another to subsist, as it is one thing to God to be, another to be the Father or the Lord (for that which He is, is spoken in respect to Himself, but He is called Father in relation to the Son, and Lord in relation to the creature which serves Him); therefore He subsists relatively, as He begets relatively, and bears rule relatively: so then substance will be no longer substance, because it will be relative. For as from being, He is called essence, so from subsisting, we speak of substance. But it is absurd that substance should be spoken relatively, for everything subsists in respect to itself; how much more God?