Supererogation

"You are perturbed over Christ's injunction in Matthew 5, "Do not resist evil, but make friends with your accuser; and if any one should take your coat, let him have your cloak as well." ... The sophists in the universities have also been perplexed by these texts. ... In order not to make heathen of the princes, they taught that Christ did not demand these things but merely offered them as advice or counsel to those who would be perfect. So Christ had to become a liar and be in error in order that the princes might come off with honor, for they could not exalt the princes without degrading Christ—wretched blind sophists that they are. And their poisonous error has spread thus to the whole world until everyone regards these teachings of Christ not as precepts binding on all Christians alike but as mere counsels for the perfect."

"Men must continue to condemn themselves not only for their failure to do what they could, but also for their failure to perform what they could not, for their denial of the absolute good whose categorical demands were laid upon their incapable will."

"When we buy new clothes not to keep ourselves warm but to look "well-dressed" we are not providing for any important need. We would not be sacrificing anything significant if we were to continue to wear our old clothes, and give the money to famine relief. By doing so, we would be preventing another person from starving. It follows from what I have said earlier that we ought to give money away, rather than spend it on clothes which we do not need to keep us warm. To do so is not charitable, or generous. Nor is it the kind of act which philosophers and theologians have called "supererogatory"—an act which it would be good to do, but not wrong not to do. On the contrary, we ought to give the money away, and it is wrong not to do so."