Article 8 — Whether there is any diversity in God

The eighth point of inquiry is whether there is any diversity in God. (Parallel texts: ST I.31.3; In I Sent. 9.1; 19.1.1, ad 2; 24.2.1.)

Obj. 1: And it seems there is. For according to the Philosopher, unity of substance makes things the same, whereas multitude in substance makes things diverse. (Aristotle, Metaphysics 5.9, 1018a9–17.) Now, in God there is multitude according to substance; thus, Hilary says that the Father, Son, and Holy Spirit are three in substance, one in harmony. (Hilary of Poitiers, On Synods 12.31–33 (PL 10:504–6).) Therefore, there is diversity in God.

Obj. 2: According to the Philosopher, the diverse is spoken of in an absolute way, whereas difference is spoken of relatively; wherefore all that differs is diverse, but not everything that is diverse is different. (Aristotle, Metaphysics 10.6, 1056b32–1057a17.) Now, it is granted that there is difference in God, since Damascene says: we acknowledge a difference between the persons in the three properties, namely, paternity, filiation, and procession. (John Damascene, On the Orthodox Faith 3.5 (PG 94:999–1000).) Therefore, there is diversity in God.

Obj. 3: Accidental difference only makes a thing other, whereas substantial difference makes another, that is, a diverse, thing. Since, then, in God there is difference, which must be a substantial difference, seeing that it cannot be an accidental difference, there must be diversity here.

Obj. 4: Multitude is caused by division, as was stated above. (Q. 9, a. 7, ad 15.) Now, where there is division there follows diversity. Therefore, in God, since there is multitude, there must be diversity.

Obj. 5: The same and the diverse are an adequate division of being. Now, the Father is not the same as the Son, for it is not granted that in begetting the Son he begets himself as God. Therefore, the Son is diverse from the Father.

On the contrary (1), Hilary says: in God nothing is new, nothing diverse, nothing foreign, nothing separable. (Hilary of Poitiers, On the Trinity 7.39 (PL 10:231–33).)

Furthermore (2), Ambrose says: the Father and the Son are one in divine nature, nor is there any substantial difference in them, nor any diversity whatsoever. (Ambrose, De fide 1.2, para. 18–19 (PL 16:533).)

I answer that, as Jerome says, (Jerome, To Pammachius, Against John of Jerusalem (PL 23:355–96).) a disordered use of terms uttered leads to heresy. Wherefore, in speaking of the divine, we must so speak to avoid any occasion of error. Now, about the divine nature there are two errors especially to be avoided by those who would discuss the unity and Trinity within the divine: namely, the error of Arius, who denied the unity of the essence and asserted a difference between the essence of the Father and that of the Son; and the error of Sabellius, who denied the plurality of the persons and asserted that the Father is the same as he who is the Son.

Accordingly, to guard against the error of Arius there are four points on which we must be wary in confessing our belief. First, diversity, which is incompatible with the unity of essence that we acknowledge when we say there is one God; second, division, which is incompatible with the divine simplicity; third, inequality, which is incompatible with the equality of the divine persons; fourth, that we do not believe the Son to be alien to the Father, whereby we would deny their likeness.

Again, against the error of Sabellius, four points call for caution. First, singularity, which excludes communicability of the divine nature; second, the word only, which excludes the real distinction of the persons; third, confusion, which excludes the order existing between the divine persons; fourth, solitude, which excludes the fellowship of the divine persons.

Accordingly, against diversity, we acknowledge the unity of the essence; against division, its simplicity; against inequality, their equality; against alienation, their likeness; against singularity of persons, a plurality; against only one, distinction; against confusion, discreteness; and against solitude, the harmony and bond of love.

Reply Obj. 1: In the words quoted, “substance” is taken for the hypostasis, not for the essence, the multiplication of which causes diversity.

Reply Obj. 2: Although some doctors of the Church use the term “difference” in reference to God, it should not be employed commonly nor should it be enlarged upon, for “difference” denotes a distinction according to form, which is impossible in God since God’s form is the divine nature, according to Augustine. Rather, we must explain the term “difference” as standing for a distinction that indicates the least distinction; for some things are said to be distinct even according to their relations or only according to mere account. So too, if we meet with the term “diversity” in connection with God, we must explain it in the same way: for instance, if we find it stated that the person of the Father is diverse from that of the Son, we must take “diverse” to mean distinct. Yet in the divine, we must be more wary of using the word “diverse” than the word “different,” because diversity pertains more to an essential division. For any multiplication whatsoever of forms makes a difference, whereas diversity arises only from substantial forms.

Reply Obj. 3: Though there is no accident in God, there is relation; and relative opposition causes distinction but not diversity in God.

Reply Obj. 4: Though properly speaking there is no division in God, there is distinction there through the relations, and this suffices for a number of persons.

Reply Obj. 5: The Son is the same God as the Father, yet it cannot be said that the Father in begetting the Son begot himself as God; because “himself,” since it is reflexive, refers to the same supposit, whereas the Father and the Son are two supposits in the divine.