4:11-12 The Lord also said that when this invasion would come it would descend like a violent wind from the north. It would be far more severe than an ordinary attack that the prophet compared to a gentle breeze that would winnow the grain of the people, namely, discipline them gently. This "wind"would come at Yahweh's command and would be the instrument of God's judgment on the people. They were all too familiar with such devastating winds, or siroccos, that blew almost unbearable heat and dust into Judah from the Arabian desert (cf. Gen. 41:6; Jon. 4:8).
4:13 Jeremiah reflected on the great power of God to bring judgment. He has the power to bring judgment as He has power to build clouds that bring rain. The approaching enemy was like a bank of storm clouds growing in the north (cf. Ezek. 38:16). The coming whirlwind was like a chariot on which the Lord rode to fight (cf. Isa. 5:28; 66:15). He can act even faster than eagles can fly. The foe would swoop down suddenly (cf. Hab. 1:8). Consequently, Judah was in big trouble.
4:14 The prophet appealed to his people to cleanse their hearts so God would be merciful to them. There was still time for repentance. The people needed to get rid of their wicked thoughts that had marked them for so long.
4:15 Already a voice, probably that of a watchman, from Dan, in the far north, and from Mount Ephraim, in the north but much closer to Judah, was heard warning of the coming invader. Mount Ephraim is a reference to the mountains in the territory of Ephraim.121This voice may refer to the testimony of the Northern Kingdom that had already been overrun by another similar invader from the north, Assyria.
4:16 The Lord continued to tell Jeremiah to announce to all nations, as well as to Jerusalem, that besiegers were coming from a distant country and would lift their battle cries against Jerusalem.
4:17 This enemy would surround the capital and observe the city carefully, as a watchman stood guard over his field to detect any possible irregularities. This invasion would come on Jerusalem because the people had rebelled against Yahweh.
4:18 God's people had brought this punishment on themselves by breaking the Mosaic Covenant. God was not acting arbitrarily. Their evil had been great, but it had not moved them to repent.