John 12:45

"He that believeth on Me, believeth not on Me, but on Him that sent Me." As though He had said, "Why fear ye to believe on Me? Faith passeth to the Father through Me, as doth also unbelief." See how in every way He showeth the unvaryingness of His Essence. He said not, He that believeth "Me," lest any should assert that He spake concerning His words; this might have been said in the case of mere men, for he that believeth the Apostles, believeth not them, but God. But that thou mightest learn that He speaketh here of the belief on His Essence, He said not, "He that believeth My words," but, "He that believeth on Me." "And wherefore," saith some one, "hath He nowhere said conversely, He that believeth on the Father, believeth not on the Father but on Me?" Because they would have replied, "Lo, we believe on the Father, but we believe not on thee." Their disposition was as yet too infirm. Anyhow, conversing with the disciples, He did speak thus: "Ye believe on the Father, believe also on Me" (c. xiv. 1); but seeing that these then were too weak to hear such words, He leadeth them in another way, showing that it is not possible to believe on the Father, without believing on Him. And that thou mayest not deem that the words are spoken as of man, He addeth, "He that seeth Me, seeth Him that sent Me." What then! Is God a body? By no means. The "seeing" of which He here speaketh is that of the mind, thence showing the Consubstantiality. And what is, "He that believeth on Me"? It is as though one should say, "He that taketh water from the river, taketh it not from the river but from the fountain"; or rather this image is too weak, when compared with the matter before us.

(Tr. liv. 2) He signifies to them that He is more than He appears to be, (for to men He appeared but a man; His Godhead was hid.) Such as the Father is, such am I in nature and in dignity; He that believeth on Me, believeth not on Me, i. e. on that which He sees, but on Him that sent Me, i. e. on the Father. [1He that believes in the Father must believe in Him as the Father, i. e. must believe that He has a Son; and reversely, he who believes in the Son thereby believes in the Father.] And again, if any one thinks that God has sons by grace, but not a Son equal and coeternal with Himself, neither does he believe 2on the Father, who sent the Son; because what he believes on is not the Father who sent Him. (c. 3.). And to show that He is not the Son, in the sense of one out of many, a son by grace, but the Only Son equal to the Father, He adds, And He that seeth Me, seeth Him that sent Me; so little difference is there between Me and Him that sent Me, that He that seeth Me, seeth Him. Our Lord sent His Apostles, yet none of them dared to say, He that believeth on Me. We believe an Apostle, but we do not believe on an Apostle. Whereas the Only Begotten says, He that believeth on Me, doth not believe on Me, but on Him that sent Me. Wherein He does not withdraw the believer's faith from Himself, but gives him a higher object than the form of a servant, for that faith.

"Jesus cried, and said, He that believeth on me, believeth not on me, but on Him that sent me; and he that seeth me, seeth 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 believeth on me, believeth 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 believeth on me, believeth not on me," that is, merely on what he seeth of me, "but on Him that sent me," that is, on the Father. But he that believeth on the Father, must believe that He is the Father; and he that believeth on Him as the Father, must believe that He has a Son; and in this way, he that believeth on the Father, must believe on the Son. And, accordingly, after saying, "He that believeth on me, believeth not on me, but on Him that sent me," that it might not be thought that He would have the Father so understood, as if He were the Father only of many sons regenerated by grace, and not of the only-begotten Word, His own co-equal, He immediately added, "And he that seeth me, seeth Him that sent me." Does He say here, He that seeth me, seeth not me, but Him that sent me, as He had said, "He that believeth me, believeth not on me, but on Him that sent me"? For He uttered the former of these words, that He might not be believed on merely as He then appeared, that is, as the Son of man; and the latter, that He might be believed on as the equal of the Father. He that believeth on me, believeth not merely on what He sees of me, but believeth on Him that sent me. Or, when he believeth on the Father, who begat me, His own co-equal, let him believe on me, not as he seeth me, but as [he believeth] on Him that sent me; for so far does the truth, that there is no distance between Him and me, reach, that He who seeth me, seeth Him that sent me.