Proverbs 27:19-23

As in water face answereth to face, so the heart of man to man.

Hell and destruction are never full; so the eyes of man are never satisfied.

As the fining pot for silver, and the furnace for gold; so is a man to his praise.

Though thou shouldest bray a fool in a mortar among wheat with a pestle, yet will not his foolishness depart from him.

Be thou diligent to know the state of thy flocks, and look well to thy herds.