1. He must show them this by a sign; for that stupid people needed to be taught as children are. The comparison made use of is that of a boiling pot. This agrees with Jeremiah's vision many years before, when he first began to be a prophet, and probably was designed to put them in mind of that (Jer. i. 13, I see a seething pot, with the face towards the north; and the explanation of it, v. 15, makes it to signify the besieging of Jerusalem by the northern nations); and, as this comparison is intended to confirm Jeremiah's vision, so also to confront the vain confidence of the princes of Jerusalem, who had said (ch. xi. 3), This city is the caldron and we are the flesh, meaning, "We are as safe here as if we were surrounded with walls of brass." "Well," says God, "it shall be so; you shall be boiled in Jerusalem, as the flesh in the caldron, boiled to pieces; let the pot be set on with water in it (v. 4); let it be filled with the flesh of the choice of the flock (v. 5), with the choice pieces (v. 4), and the marrow-bones, and let the other bones serve for fuel, that, one way or other, either in the pot or under it, the whole beast may be made use of." A fire of bones, though it be a slow fire (for the siege was to be long), is yet a sure and lasting fire; such was God's wrath against them, and not like the crackling of thorns under a pot, which has noise and blaze, but no intense heat. Those that from all parts of the country fled into Jerusalem for safety would be sadly disappointed when the siege laid to it would soon make the place too hot for them; and yet there was not getting out of it, but they must be forced to abide by it, as the flesh in a boiling pot.