5 But what is meant, says he, in the other passage: “This is God, and there shall none other be accounted of in comparison of Him?” That said he rightly. For in comparison of the Father who shall be accounted of? But he says: “This is our God; there shall none other be accounted of in comparison of Him. He has found out all the way of knowledge, and has given it unto Jacob His servant, and to Israel His beloved.” He says well. For who is Jacob His servant, Israel His beloved, but He of whom He cries, saying, “This is my beloved Son, in whom I am well pleased: hear Him?”
Having received, then, all knowledge from the Father, the perfect Israel, the true Jacob, afterward did show Himself upon earth, and conversed with men. And who, again, is meant by Israel but a man who sees God? and there is no one who sees God except the Son alone, the perfect man who alone declares the will of the Father. For John also says, “No man has seen God at any time; the only-begotten Son, which is in the bosom of the Father, He has declared Him.” And again: “He who came down from heaven testifies what He has heard and seen.” This, then, is He to whom the Father has given all knowledge, who did show Himself upon earth, and conversed with men.
Source: Against the Heresy of Noetus (New Advent)