Q. 9. How many persons are there in the Godhead?
A. There be three persons in the Godhead, the Father, the Son, and the Holy Ghost; and these three are one true, eternal God, the same in substance, equal in power and glory; although distinguished by their personal properties.
We have a couple of more posts before we get to a discussion of how God works in his creation. For now the Scripture references on Q9 are excellent in supporting what we often call the Trinity. Though word Trinity is not in the Bible it’s meaning is clearly seen.
Matt. 3:16–17. And Jesus, when he was baptized, went up straightway out of the water: and, lo, the heavens were opened unto him, and he saw the Spirit of God descending like a dove, and lighting upon him: and lo a voice from heaven, saying, This is my beloved Son, in whom I am well pleased. Matt. 28:19. Go ye therefore, and teach all nations, baptizing them in the name of the Father, and of the Son, and of the Holy Ghost. 2 Cor. 13:14. The grace of the Lord Jesus Christ, and the love of God, and the communion of the Holy Ghost, be with you all. Amen.
Vos makes the argument against contradiction using logic.
Does the doctrine of the Trinity contradict itself? No. There is no contradiction involved, although opponents of the doctrine never weary of calling it “contradictory.” The doctrine teaches that God is one in one sense, and three in a different sense. He is one in substance and three in persons. While we may freely admit that this is a mystery which baffles the human mind, still it does not involve a contradiction. It would be contradictory if we were to affirm that God is both one and three in the same sense, that is, if we were to say that there is only one person in the Godhead and at the same time there are three persons in the Godhead. This would be an absurdity, but no Christian creed sets forth any such view of the matter.