Chasidut zu Mischlej 29:17

It seems to me that we don’t have to speak to you any more about this, because these holy words have already done their work and had the proper effect upon you. But anyhow, we will add a few words and thereby fulfill the verse (Mishlei, 29:17), “correct you son, and he shall give you rest." The Gemara (Makkos, 8b) adds to this, “even if he has already learned enough.”