v1: The new message; Watch out! Flee! Disaster and great destruction was on the way. A mighty army was coming from the north, see v22-23. These words are addressed directly to Jerusalem and Benjamin, in whose territory Jerusalem lay.
v2-3: The delightful Zion, which God had intended should enjoy peace and security, was to be surrounded by enemy armies.
v4-5: The Gentile nations joined together to attack Jerusalem. They attacked by day and night.
v6-7: The nations were effectively instructed by God to attack Jerusalem. The reasons were made clear; oppression, wickedness, violence, destruction (or plundering). She is described as sick and wounded, see Is 1.5-6.
v8: The opportunity to repent. Jeremiah was the eleventh hour prophet, for the nation was on the very verge of judgment.
v9: Judah to be thoroughly gleaned, leaving nothing behind. The land would be left desolate.
v10: There was no delight in the word of the Lord. No one took to heart the messages from God.
v11-12: The fury of the Lord, "I cannot hold it in," or restrain it. Judgment was inevitable, and would fall very soon. Families and houses and land would all fall before the invading army.
v13: People characterised by covetousness, and by falsehood.
v14: The false prophets, telling the people what they wanted to hear, not what they needed to hear.
Their false message was of peace; they taught that the city would be delivered from Babylon's attacks, see 23.17.
Jeremiah's truth may have been uncomfortable, and less popular, but it was necessary that it was proclaimed.
v15: There was no shame, even at their serious sins.
v16: The prophets told the people to think back to better times. Their strong verbal tradition ensured that the good times were accurately remembered. They could re-enter those good paths only by going God's way; in that was rest for their souls.
v17: Jeremiah was not the only prophet; God had appointed a number of watchmen. But the people's reaction had been consistent, "We will not listen."
v18-19: Gentile nations would realise that God's judgment had fallen on His people.
v20: Sacrifices continued, even to the importing of incense, but these were futile without teal devotion. Formality is useless without obedience.
v21: God put obstacle before them, which they would stumble over.
v22-23: The Babylonian army, see Hab 1.5-10. This army was approaching from the north, as in 1.13-14.
v24-26: Even before the army arrived the people grew faint and fearful.
v27: Jeremiah the assayer, testing the people's heart. This was part of his calling, to test their heart and motive.
v28: The bad metal of Judah, bronze and iron; they needed to be refined, for they were rebels, slanderers, corrupters, useless alloy mixed with the precious.
v29: The bellows blow fiercely, as God's word was delivered. The lead, the impurity, was burned. But this was in vain, as the wicked were not drawn off; they remained unwilling to be purged by God.
v30: As a result they are rejected by God, as impure silver. The necessary cleansing was not achieved except by the 70 years suffering in captivity.