Tractates on the Gospel of John

² While matters were in this state, and His own passion was now at hand, “Jesus cried, and said,” as our lesson today commences, “He that believes in me, believes not on me, but on Him that sent me; and he that sees me, sees Him that sent me.” He had already said in a certain place, “My doctrine is not mine, but His that sent me.” Where we understood that He called His doctrine just what He is Himself, the Word of the Father; and in saying, “My doctrine is not mine, but His that sent me,” implied this, that He was not of Himself, but had His being from another. For He was God of God, the Son of the Father: but the Father is not God of God, but God, the Father of the Son.

And now when He says, “He that believes in me, believes not on me, but on Him that sent me,” how else are we to understand it, but that He appeared as man to men, while He remained invisible as God? And that none might think that He was no more than what they saw of Him, He indicated His wish to be believed on, as equal in character and rank with the Father, when He said, “He that believes in me, believes not on me,” that is, merely on what he sees of me, “but on Him that sent me,” that is, on the Father.

But he that believes in the Father, must believe that He is the Father; and he that believes in Him as the Father, must believe that He has a Son; and in this way, he that believes in the Father, must believe in the Son. But let no one believe about the only-begotten Son just what they believe about those who are called the sons of God by grace and not by nature, as the evangelist says, “He gave them power to become the sons of God,” and according to what the Lord Himself also mentioned, as declared in the law, “I said, You are gods; and all of you children of the Most High:” because He said, “He that believes in me, believes not on me,” to show that the whole extent of our faith in Christ should not be limited by His manhood.

He therefore, He says, believes in me, who does not believe in me merely according to what he sees of me, but on Him that sent me: so that, believing thus on the Father, he may believe that He has a Son co-equal with Himself, and then attain to a true faith in me. For if one should think that He has sons only according to grace, who are certainly no more than His creatures, and not the Word, but those made by the Word, and that He has no Son co-equal and co-eternal with Himself, ever born, alike incommutable, in nothing dissimilar and inferior, then he believes not on the Father who sent Him, for the Father who sent Him is no such conception as this.