24 The fifth book follows in reply the sequence of heretical assertion. They had falsely declared that they followed the law in the sense which they assigned to the unity of God, and that they had proved from it that the true God is of one Person; and this in order to rob the Lord Christ of His birth by their conclusion concerning the One true God, for birth is the evidence of origin. In answer I assert, step by step, what they deny; for from the Law and the Prophets I demonstrate that there are not two gods, nor one isolated true God, neither perverting the faith in the Divine unity nor denying the birth of Christ. And since they say that the Lord Jesus Christ, created rather than born, bears the Divine Name by gift and not by right, I have proved His true Divinity from the Prophets in such a way that, He being acknowledged very God, the assurance of His inherent Godhead shall hold us fast to the certainty that God is One.
Source: On the Trinity (New Advent)