I. He must tell them how very bad they really were, v. 1. 1. He must deal faithfully and plainly with them. "Though they are called the people of God and the house of Jacob, though they wear an honourable title and character, by which they are interested in many glorious privileges, yet do not flatter them, but show them their transgressions and their sins, be particular in telling them their faults, what sins are committed among them, which they do not know of, nay, what sins are committed by them which they do not acknowledge to be sins; though in some things they are reformed, let them know that in other things they are still as bad as ever. Show them their transgressions and their sins, that is, all their transgressions in their sins, their sins and all the aggravations of them," Lev. xvi. 21. Note, (1.) God sees sin in his people, in the house of Jacob, and is displeased with it. (2.) They are often unapt and unwilling to see their own sins, and need to have them shown them, and to be told, Thus and thus thou hast done. 2. He must be vehement and in good earnest herein, must cry aloud, and not spare, not spare them (not touch them with his reproofs as if he were afraid of hurting them, but search the wound to the bottom, lay it bare to the bone), not spare himself or his own pains, but cry as loud as he can; though he spend his strength and waste his spirits, though he get their ill-will by it and get himself into an ill name, yet he must not spare. He must lift up his voice like a trumpet, to make those hear of their faults that were apt to be deaf when admonition was addressed to them. He must give his reproofs in the most powerful and pressing manner possible, as one who desired to be heeded. The trumpet does not give an uncertain sound, but, though loud and shrill, is intelligible; so must his alarms be, giving them warning of the fatal consequences of sin, Ezek. xxxiii. 3.