The Instructor 1.8.66

Just as the hortatory and consoling kind of speech belongs to deliberative speech, so the reproaching and rebuking kind belongs to the speech of praise [and praising]. This kind is an art of censure; and censure is a sign of goodwill, not of hatred. Both friend and enemy reproach, but the enemy mocks, while the friend means well. So the Lord does not revile human beings out of hatred; though he could have destroyed them for their own faults, he even suffered for us. For as a good Instructor, very skillfully, he takes on censure through rebuke, rousing the sluggishness of the mind with reproach as with a whip, and then in turn tries to encourage the same people. Those whom praise did not encourage, blame has spurred on; and those whom blame did not call out to salvation, as if they were dead, reproach raises up to the truth. “For whips and discipline are at every time wisdom. He who teaches a fool glues together a potsherd,” it says, bringing the earth to feeling and sharpening the despairing to understanding. So it clearly added, “rousing a sleeper from deep sleep,” which of all things is most like death. And the Lord himself shows this most clearly of himself, speaking figuratively of his many-sided and most beneficial care, when he said, “I am the true vine, and my Father is the vinedresser,” and then added, “Every branch in me that does not bear fruit he takes away, and every branch that bears fruit he prunes, that it may bear more fruit.” For an unpruned vine runs wild with wood, and so does a human being; the Word, the knife, prunes his wanton shoots, compelling his desires to bear fruit, not to lust.