Thomas Aquinas, on 1Cor 11:31

“But if we would judge ourselves, we should not be judged.”

“Then when he says, But if we judged, he assigns two reasons for the above sign: the first is taken on our part; the second on God's part (v. 32). On our part the cause of divine punishment is from negligence, because we neglect to punish ourselves for sins committed. Hence he says that if we judged ourselves truly by rebuking and punishing our sins, we should not be judged, i.e., not punished by the Lord either later in the future or even in the present. But on the other hand it says above (4:3): "I do not even judge myself" and in Rom (14:22): "Blessed is he that does not judge himself." The answer is that someone can judge himself in three ways: in one way by examination, and in this way one ought to judge himself both as to past works and as to future ones, according to Gal (6:4): "Let each one prove his own work." In another way by absolving himself decisionally as though judging himself innocent as to the past; and according to this, no one should judge himself, namely, that he judge himself innocent, according to Jb (9:20): "Though I am innocent, my own mouth would condemn me; though I am blameless, he would prove me perverse." In a third way by reprehending, namely, that he did something he judges evil. In this way is understood the statement: "Blessed is he who does not judge himself for what he approves." But as to things already done, each one ought to judge himself by blaming and punishing oneself for evil deeds. Hence it says in Jb (13:15): "I will defend my ways to his face" and (23:4): "I would lay my case before him and fill my mouth with arguments." In the book On Penance, Augustine says of this judgment: "Let the image of the future judgment play before your eyes and let a man rise up against himself before his own face, and having made a judgment in his heart, let thought be the accuser and conscience the witness and the heart executioner. Then let the blood of the confessing spirit break out in tears. Finally, from the mind itself let such a sentence issue that the man judges himself unworthy to partake of the body and blood of the Lord."”

Imported from an open dataset — not yet checked against the printed edition.