15. Their starting-point is this; We confess, they say, One only God, because Moses says, Hear, O Israel, the Lord thy God is One Deut. vi. 4.. But is this a truth which anyone has ever dared to doubt? Or was any believer ever known to confess otherwise than that there is One God from Whom are all things, One Majesty which has no birth, and that He is that unoriginated Power? Yet this fact of the Unity of God offers no chance for denying the Divinity of His Son. For Moses, or rather God through Moses, laid it down as His first commandment to that people, devoted both in Egypt and in the Desert to idols and the worship of imaginary gods, that they must believe in One God. There was truth and reason in the commandment, for God, from Whom are all things, is One. But let us see whether this Moses have not confessed that He, through Whom are all things, is also God. God is not robbed, He is still God, if His Son share the Godhead. For the case is that of God from God, of One from One, of God Who is One because God is from Him. And conversely the Son is not less God because God the Father is One, for He is the Only-begotten Son of God; not eternally unborn, so as to deprive the Father of His Oneness, nor yet different from God, for He is born from Him. We must not doubt that He is God by virtue of that birth from God which proves to us who believe that God is One; yet let us see whether Moses, who announced to Israel, The Lord thy God is One, has also proclaimed the Godhead of the Son. To make good our confession of the Divinity of our Lord Jesus Christ we must employ the evidence of that same witness on whom the heretics rely for the confession of One Only God, which they imagine to involve the denial of the Godhead of the Son.