6 For “no man,” he says, “has seen God at any time,” unless “the only-begotten Son of God, which is in the bosom of the Father, He has declared [Him].” For He, the Son who is in His bosom, declares to all the Father who is invisible. Wherefore they know Him to whom the Son reveals Him; and again, the Father, by means of the Son, gives knowledge of His Son to those who love Him. By whom also Nathanael, being taught, recognised [Him], he to whom also the Lord bore witness, that he was “an Israelite indeed, in whom was no guile.” The Israelite recognised his King, therefore did he cry out to Him, “Rabbi, You are the Son of God, You are the King of Israel.” By whom also Peter, having been taught, recognised Christ as the Son of the living God, when [God] said, “Behold My dearly beloved Son, in whom I am well pleased: I will put my Spirit upon Him, and He shall show judgment to the Gentiles. He shall not strive, nor cry; neither shall any man hear His voice in the streets. A bruised reed shall He not break, and smoking flax shall He not quench, until He send forth judgment into contention; and in His name shall the Gentiles trust.”
Source: Adversus haereses (New Advent)