19. Since no one is perfect,  does it follow that no one has the right to reprehend one’s neighbor?

Of  course not,  since each of you must  labor for the progress of all, especially those whose tutelage has been entrusted to you. But you must reprehend others with moderation, with a useful purpose, and not as is usually done: for the pleasure of denigrating them. In this latter instance, criticism is wickedness; in the former, it is a duty, which charity commands to be achieved with all the care possible. Moreover, the criticism one casts at others must at the same time be directed at oneself, asking if one does not deserve it more.

St. Louis (Paris, 1860)