3 But how are we to understand, “You shall see me no more”? For He says not, I go to the Father, and you shall not see me, so as to be understood as referring to the interval of time when He would not be seen, whether short or long, but at all events terminable; but in saying, “You shall see me no more,” as if a truth announced beforehand that they would never see Christ in all time coming. Is this the righteousness we speak of, never to see Christ, and yet to believe in Him; seeing that the faith whereby the just lives is commended on the very ground of believing that the Christ whom it sees not meanwhile, it shall see some day? Once more, in reference to this righteousness, are we to say that the Apostle Paul was not righteous when confessing that He had seen Christ after His ascension into heaven, which was undoubtedly the time of which He had already said, “You shall see me no more”? Was Stephen, that hero of surpassing renown, not righteous in the spirit of this righteousness, who, when they were stoning him, exclaimed, “Behold, I see the heavens opened, and the Son of man standing on the right hand of God”? What, then, is meant by “I go to the Father, and you shall see me no more,” but just this, As I am while with you now? For at that time He was still mortal in the likeness of sinful flesh. He could suffer hunger and thirst, be wearied, and sleep; and this Christ, that is, Christ in such a condition, they were no more to see after He had passed from this world to the Father; and such, also, is the righteousness of faith, whereof the apostle says, “Though we have known Christ after the flesh, yet now henceforth know we Him no more.” This, then, He says, will be your righteousness whereof the world shall be reproved, “because I go to the Father, and you shall see me no more:” seeing that you shall believe in me as in one whom you shall not see; and when you shall see me as I shall be then, you shall not see me as I am while with you meanwhile; you shall not see me in my humility, but in my exaltation; nor in my mortality, but in my eternity; nor at the bar, but on the throne of judgment: and by this faith of yours, in other words, your righteousness, the Holy Spirit will reprove an unbelieving world.
4. He will also reprove it “of judgment, because the prince of this world is judged.” Who is this, save he of whom He says in another place, “Behold, the prince of the world comes, and shall find nothing in me;” that is, nothing within his jurisdiction, nothing belonging to him; in fact, no sin at all? For thereby is the devil the prince of the world. For it is not of the heavens and of the earth, and of all that is in them, that the devil is prince, in the sense in which the world is to be understood, when it is said, “And the world was made by Him;” but the devil is prince of that world, whereof in the same passage He immediately afterwards subjoins the words, “And the world knew Him not;” that is, unbelieving men, wherewith the world through its utmost extent is filled: among whom the believing world groans, which He, who made the world, chose out of the world; and of whom He says Himself, “The Son of man came not to judge the world, but that the world through Him might be saved.” He is the judge by whom the world is condemned, the helper whereby the world is saved: for just as a tree is full of foliage and fruit, or a field of chaff and wheat, so is the world full of believers and unbelievers. Therefore the prince of this world, that is, the prince of the darkness thereof, or of unbelievers, out of whose hands that world is rescued, to which it is said, “You were at one time darkness, but now are you light in the Lord:” the prince of this world, of whom He elsewhere says, “Now is the prince of this world cast out,” is assuredly judged, inas much as he is irrevocably destined to the judgment of everlasting fire. And so of this judgment, by which the prince of the world is judged, is the world reproved by the Holy Spirit; for it is judged along with its prince, whom it imitates in its own pride and impiety. “For if God,” in the words of the Apostle Peter, “spared not the angels that sinned, but thrust them into prisons of infernal darkness, and gave them up to be reserved for punishment in the judgment,” how is the world otherwise than reproved of this judgment by the Holy Spirit, when it is in the Holy Spirit that the apostle so speaks? Let men, therefore, believe in Christ, that they be not convicted of the sin of their own unbelief, whereby all sins are retained: let them make their way into the number of believers, that they be not convicted of the righteousness of those, whom, as justified, they fail to imitate: let them beware of that future judgment, that they be not judged with the prince of the world, whom, judged as he is, they continue to imitate. For the unbending pride of mortals can have no thought of being spared itself, as it is thus called to think with terror of the punishment that overtook the pride of angels.
Source: Tractates on the Gospel of John (New Advent)