…When you see your friend doing countless evil things, do you prefer his favor over his well-being? Do not, I beg you. No evidence proves true friendship more than when we never overlook the sins of our friends. Did you see them doing something wrong? Try to correct them. For example, are they guilty of covetousness? Call them out. Did you see them being wronged? Stand up and defend them. It is not they who are benefited most, but you. This is why we are friends, that we might be of use to each other. A man will be more open to hear what a friend has to say than someone on the street. He might be suspicious of others, even a teacher, but not a friend.