3. For this reason we believe also in His Son, that is to say, God the Father Almighty's, "His Only Son, our Lord." When thou hearest of the Only Son of God, acknowledge Him God. For it could not be that God's Only Son should not be God. What He is, the same did He beget, though He is not that Person Whom He begot. If He be truly Son, He is that which the Father is; if He be not that which the Father is, He is not truly Son. Observe mortal and earthly creatures: what each is, that it engendereth. Man besets not an ox, sheep besets not dog, nor dog sheep. Whatever it be that begetteth, that which it is, it begetteth. Hold ye therefore boldly, firmly, faithfully, that the Begotten of God the Father is what Himself is, Almighty. These mortal creatures engender by corruption. Does God so beget? He that is begotten mortal generates that which himself is; the Immortal generates what He is: corruptible begets corruptible, Incorruptible begets Incorruptible: the corruptible begets corruptibly, Incorruptible, Incorruptibly: yea, so begetteth what Itself is, that One begets One, and therefore Only. Ye know, that when I pronounced to you the Creed, so I said, and so ye are bounden to believe; that we "believe in God the Father Almighty, and in Jesus Christ His Only Son." Here too, when thou believest that He is the Only, believe Him Almighty: for it is not to be thought that God the Father does what He will, and God the Son does not what He will. One Will of Father and Son, because one Nature. For it is impossible for the will of the Son to be any whit parted from the Father's will. God and God; both one God: Almighty and Almighty; both One Almighty. c4. We do not bring in two Gods as some do, who say, "God the Father and God the Son, but greater God the Father and lesser God the Son." They both are what? Two Gods? Thou blushest to speak it, blush to believe it. Lord God the Father, thou sayest, and Lord God the Son: and the Son Himself saith, "No man can serve two Lords." [1768] In His family shall we be in such wise, that, like as in a great house where there is the father of a family and he hath a son, so we should say, the greater Lord, the lesser Lord? Shrink from such a thought. If ye make to yourselves such like in your heart, ye set up idols in the "one soul." Utterly repel it. First believe, then understand. Now to whom God gives that when he has believed he soon understands; that is God's gift, not human frailness. Still, if ye do not yet understand, believe: One God the Father, God Christ the Son of God. Both are what? One God. And how are both said to be One God? How? Dost thou marvel? In the Acts of the Apostles, "There was," it says, "in the believers, one soul and one heart." [1769] There were many souls, faith had made them one. So many thousands of souls were there; they loved each other, and many are one: they loved God in the fire of charity, and from being many they are come to the oneness of beauty. If all those many souls the dearness of love [1770] made one soul, what must be the dearness of love in God, where is no diversity, but entire equality! If on earth and among men there could be so great charity as of so many souls to make one soul, where Father from Son, Son from Father, hath been ever inseparable, could They both be other than One God? Only, those souls might be called both many souls and one soul; but God, in Whom is ineffable and highest conjunction, may be called One God, not two Gods.

Footnotes:

[1768] Matt. vi.24 [1769] Acts iv.32

[1770] Charitas