Therefore the Apostle's aim was reached even without explaining how the saints will judge the world. He does not add such an explanation. But for us now this is not entirely clear.
The judge of the world is the Lord alone. When He Himself depicts the judgment, He gives us to understand that both believers and unbelievers will be subject to Him.
Having carried out the judgment, He will say to some, “Come, you blessed,” and to others, “Depart, you cursed.” How then will the saints judge, when they themselves will be judged?
To this we shall say: the Apostle's word is not false. The saints will judge the world and angels. How they will do so, we do not know. Our ignorance does not diminish the truth of the apostolic word.
But whom will such an answer satisfy? Everyone wishes to arrive at a solution. Yet since there is nothing on which to found a solution, it is unavoidable to construct suppositions. Many have been constructed.
It is not worth enumerating them. Let us take the one unanimously accepted by all our commentators. Here are Theodoret's words: “He said ‘they will judge’ in place of ‘they will condemn.’
The following words make this understood: ‘if by you,’ εν υμιν, ‘the world is judged.’ Thus ‘the men of Nineveh’ and ‘the queen of the South’ will condemn that generation (Mt 12:41-42).
Thus the twelve Apostles will judge the twelve tribes of Israel (Mt 19:28), that is, they will condemn them. They will condemn them because they themselves came from them, believed in the Lord, underwent countless forms of death, and did not deny faith in Him.
So also those who believed from among the Gentiles will condemn those who did not believe the saving preaching.”
Here is what Chrysostom says: “The saints will judge, not by sitting and demanding an account, but by condemning. The Apostle expresses this with the words: ‘if by you the world is judged.’
He did not say, ‘from you,’ but ‘by you,’ εν υμιν, that is, by you, in your holiness. As the Lord also said: ‘The queen of the South will rise and condemn this generation,’ and: ‘The men of Nineveh will rise and condemn this generation’ (Mt 12:41-42).
They see the same sun as we do and share in the same things. Yet if we prove to be believers and they unbelievers, then it will be impossible for them to appeal to ignorance.
We shall condemn them by what we have done. And many similar ways of condemnation will be found then.” So also Saint John of Damascus, Oecumenius, Photius in Oecumenius, and Theophylact.
The last addition of Chrysostom shows that other ways are also possible by which unbelievers are condemned by believers. But all are condemnations, not judgment. Let us stop at this solution.
Great weight is given to it by εν υμιν, “in you,” as though in your person, or by pointing to you, the judge will pronounce judgment, and by you He will be justified in His judgment.
If so, Saint Paul says further, “are you unworthy of the least courts?” As though he said: “Your conduct brings you shame and inexpressible dishonor.
The Corinthians were probably ashamed to be judged before their own judges. Therefore he says: on the contrary, be ashamed that you are judged before those outside. Their courts are insignificant, not yours” (Chrysostom).