Verses 1-4 set a condition: if Israel returns, let her return to the Lord, remove her idols and swear by the Lord in truth. So he tells them to break up their fallow ground and to circumcise their hearts, lest his wrath break out like fire.
Verses 5-18 change tone. The trumpet is blown and the cry goes out that all should flee to the fortified cities, for evil comes from the north. A lion has come up from his thicket, a destroyer of nations. It is announced that kings and priests will lose heart. Jeremiah cries that the Lord has deceived this people by promising peace while the sword reaches the throat. A hot wind comes from the desert. A voice from Dan and from the hills of Ephraim announces that besiegers are coming from a distant land. God asks Jerusalem to wash her heart from evil, and concludes that her own conduct has brought this on her.
In verses 19-22 the prophet speaks in pain: he writhes in anguish, his heart pounds, and he cannot keep silent because he hears the sound of the trumpet and the alarm of war. The Lord says his people are foolish, wise to do evil but not to do good. In verses 23-28 Jeremiah sees the earth formless and empty, with no light in the heavens, the mountains quaking, no one left and the birds fled. It is a picture of creation undone. The Lord declares that the whole land will be desolate, though he will not make a full end.
Verses 29-31 show the city fleeing at the noise of horsemen while she dresses in scarlet and decks herself with gold. Her lovers despise her. Jeremiah hears a cry like a woman in labor, saying her hands fail before the murderers.