I. What the office is to which the prophet is called: Son of man, I have made thee a watchman to the house of Israel, v. 17. The vision he saw astonished him: he knew not what to make of that, and therefore God used this plain comparison, which served better to lead him to the understanding of his work and so to reconcile him to it. He sat among the captives, and said little, but God comes to him, and tells him that will not do; he is a watchman, and has something to say to them; he is appointed to be as a watchman in the city, to guard against fire, robbers, and disturbers of the peace, as a watchman over the flock, to guard against thieves and beasts of prey, but especially as a watchman in the camp, in an invaded country or a besieged town, that is to watch the motions of the enemy, and to sound an alarm upon the approach, nay, upon the first appearance, of danger. This supposes the house of Israel to be in a military state, and exposed to enemies, who are subtle and restless in their attempts upon it; yea, and each of the particular members of that house to be in danger and concerned to stand upon their guard. Note, Ministers are watchmen on the church's walls (Isa. lxii. 6), watchmen that go about the city, Cant. iii. 3. It is a toilsome office. Watchmen must keep awake, be they ever so sleepy, and keep abroad, be it ever so cold; they must stand all weathers upon the watch-tower, Isa. xxi. 8; Gen. xxxi. 40. It is a dangerous office. Sometimes they cannot keep their post, but are in peril of death from the enemy, who gain their point if they kill the sentinel; and yet they dare not quit their post upon pain of death from their general. Such a dilemma are the church's watchmen in; men will curse them if they be faithful, and God will curse them if they be false. But it is a needful office; the house of Israel cannot be safe without watchmen, and yet, except the Lord keep it, the watchman waketh but in vain, Ps. cxxvii. 1, 2.