Oséias 1

Oséias 1:7

He says to Hosea the prophet, "I will not add any more to have mercy on the house of Israel, but as their adversary I shall oppose them. But I shall have mercy on the sons of Judah, and I shall save them by the Lord their God." The Father unmistakably gives the name of God to his Son in whom he chose us before the eternal ages. For this reason he says "their God," because the unborn God is from no one, and God the Father has given us as an inheritance to his Son. — ON THE TRINITY 4:37