12 “For,” says He, “the Father judges no man, but all judgment has He given to the Son.” A little before we were thinking that the Father does something which the Son does not, when He said, “The Father loves the Son, and shows Him all things that Himself does;” as though the Father were doing, and the Son were seeing. In this way there was creeping in upon our mind a carnal conception, as if the Father did what the Son did not; but that the Son was looking on while the Father showed what He was doing.
Then, as the Father was doing what the Son did not, just now we see the Son doing what the Father does not. How He turns us about, and keeps our mind busy! He leads us hither and there, will not allow us to remain in one place of the flesh, that by changing He may exercise us, by exercising He may cleanse us, by cleansing He may render us capable of receiving, and may fill us when made capable. What have these words to do with us? What was He speaking? What is He speaking? A little before, He said that the Father shows to the Son whatever He does.
I did see, as it were, the Father doing, the Son waiting to see; presently again, I see the Son doing, the Father idle: “For the Father judges not any man, but all judgment has He given to the Son.” When, therefore, the Son is about to judge, will the Father be idle, and not judge? What is this? What am I to understand? What dost Thou say, O Lord? You are God the Word, I am a man. Do You say that “the Father judges not any man, but has given all judgment to the Son”? I read in another place that You say, “I judge not any man; there is one who seeks and judges.” Of whom sayest Thou, “There is one who seeks and judges,” unless it be of the Father?
He makes inquisition for your wrongs, and judges for them. How is it to be understood here that “the Father judges not any man, but all judgment has He given to the Son”? Let us ask Peter; let us hear him speaking in his epistle: “Christ suffered for us,” says he, “leaving us an example that we should follow His steps; who did no sin, neither was guile found in His mouth; who, when He was reviled, reviled not again; when He suffered wrong, He threatened not, but committed Himself to Him that judges righteously.” How is it true that “the Father judges not any man, but has given all judgment to the Son”?
We are here in perplexity, and being perplexed let us exert ourselves, that by exertion we may be purified. Let us endeavor as best we may, by His own gift, to penetrate the deep secrets of these words. It may be that we are acting rashly, in that we wish to discuss and to scrutinize the words of God. Yet why were they spoken, but to be known? Why did they sound forth, but to be heard? Why were they heard, but to be understood? Let Him greatly strengthen us, then, and bestow somewhat on us so far as He may deem worthy; and if we do not yet penetrate to the fountain, let us drink of the brook.
Behold, John himself has flowed forth to us like a brook, conveyed to us the word from on high. He brought it low, and in a manner levelled it, that we may not dread the lofty One, but may draw near to Him that is low.
Source: Tractates on the Gospel of John (New Advent)