John Chrysostom

"I say it not to condemn you." How is this evident? "For I have said before," he adds, "that ye are in our hearts to die and live with you." This is the greatest affection, when even though treated with contempt, he chooseth both to die and live with them. 'For neither are ye merely in our hearts,' he says, 'but in such sort as I said. For it is possible both to love and to shun dangers, but we do not thus.' And behold here also wisdom unspeakable. …

Homily 14 on 2 Corinthians ↗

Theophylact of Ohrid

I say this not to condemn you. How is this evident? From love; for you are in our hearts. But since someone might love yet not wish to expose himself to dangers, he says: "to die together." And since there are many who do not rejoice in the prosperity of friends out of envy, he added: "and to live." The meaning of what is said is this: in dangers we do not flee from you, and in prosperity we live with you and do not envy you.

Commentary on 2 Corinthians ↗

Thomas Aquinas

Then when he says, I do not say this to condemn you, he discloses his intention. As if to say: I do not say this to condemn you, but to correct you. For past evils are wont to be recalled sometimes for condemnation, when there is no further hope of correction; and sometimes for amendment, so that they will be corrected. And this is the way he speaks here: I do not say this to condemn you: "I say this for your own benefit" (1 Cor. 7:35). …

Commentary on 2 Corinthians ↗