Verse 1
Jeremiah 21:1. The word which came to Jeremiah, when King Zedekiah sent unto him — The occasion of Zedekiah’s sending the message here mentioned to Jeremiah, has, by some commentators, been confounded with that in chap. 37. “But I think,” says Blaney, “they are clearly and undeniably distinct one from the other. From the reply given to that in chapter 37., it is manifest that the Chaldeans, who had been besieging Jerusalem for some time had already raised the siege, and were gone to meet the Egyptian army, leaving the Jews in great hopes that they would never return again. But the terms of this message seem to imply, that the king of Babylon had but just commenced his hostilities against Judah, of which Zedekiah informs the prophet, as of a matter that might not yet have come to his certain knowledge; and desires him to intercede with God, that he would divert the storm by some such extraordinary interposition as he had been wont to manifest in favour of his people. The answer likewise takes no notice of any siege or operations past; but simply regards the future, which it is declared should end unhappily, because God would take an active part against the inhabitants of Judah, and would deliver both their city, and also the king and his people, into the hands of their merciless enemies. The time of this transaction, therefore, I conceive to be the ninth year of Zedekiah, previous to the siege of Jerusalem, which began in the tenth mouth of that year.”

Verse 2
Jeremiah 21:2. Inquire, I pray thee, of the Lord for us — As Zedekiah was not one of the best, so he was not one of the worst of the kings of Judah. Having some reverence for God, he sends the prophet to inquire of him. Or, as the word דרשׁ, signifies, to seek or apply to God by prayer and supplication: see Isaiah 55:6. If so be the Lord will deal with us, &c. —

If he will show his wonderful power, in giving us a total deliverance from the hands of our enemies, the Chaldeans. If they had attended to the predictions of the prophets they would not have made this inquiry of Jeremiah; for all the things which had happened to them already, had been predicted by the prophets. But perhaps they flattered themselves that all God’s threatenings would not be executed; or that they had been executed already, in great numbers of them being carried into captivity, first in the reign of Jehoiakim, and afterward in that of Jehoiachin.

Verses 4-7
Jeremiah 21:4-7. Behold, I will turn back the weapons, &c. — Instead of doing execution upon your enemies, they shall hurt yourselves, and be the occasion of your own destruction. God will as visibly appear against you as if a miraculous wind were to drive back your own darts and arrows, and turn them upon yourselves. And I myself will fight against you — By the executioners of my wrath, the sword, the famine, and the pestilence. I will plainly appear on your enemies’ side, by the success I will give to their arms. And I will smite the inhabitants of this city — I the Lord will do it, and it shall evidently appear to be my work; both man and beast — Even the beasts shall perish, both those that are for food, and those that are for service in war. They shall die of a great pestilence — Which shall rage within the walls, while their enemies are encamped about them. Though the walls and gates of Jerusalem may for a time keep out the Chaldeans, they cannot keep out God’s judgments. His arrows of pestilence can reach those that think themselves safe from other arrows. And I will deliver Zedekiah, &c. — The king himself, and all the people that escape the sword, famine, and pestilence, shall fall into the hands of Nebuchadnezzar and the Chaldeans. And he shall smite them with the edge of the sword — Zedekiah himself was not put to death, but carried to Babylon, where he died: see Jeremiah 24:5. But his sons and his great men were slain by the command of Nebuchadnezzar, 2 Kings 25:7-8. “It is common in all writers to express that indefinitely which is true of the greater part of the persons concerned.” — Lowth. He shall not spare, neither have pity nor mercy — These three synonymous terms are used by way of emphasis, to express the severe revenge the Babylonians would take of them. The inhabitants of Jerusalem must indeed have been sensible at last, that they could expect little or no mercy, since they had rebelled three times against the king of Babylon.

Verses 8-10
Jeremiah 21:8-10. And unto this people thou shalt say, &c. — By the civil message which the king sent to Jeremiah it appeared that both he and the people began to have respect for him; but the reply which God obliged him to make was sufficient to crush that little respect, and to exasperate them against him more than ever. Behold, I set before you the way of life, and the way of death — Both the law and the prophets had often set before them life and death in another sense; life, if they would obey the voice of God; death, if they should persist in disobedience, Deuteronomy 30:19. But they had slighted that way of life which would have made them truly happy; to upbraid them with which the prophet here uses similar expressions, which signify, not as those of Moses, a fair proposal, but a melancholy dilemma, advising them, of two evils, to choose the least. And that lesser evil, a shameful and wretched captivity, is all the life now left for them to propose to themselves. He that abideth in this city — And trusts to it to secure him; shall die by the sword — Without the city; or by the famine, or pestilence within it. But he that goeth out, and falleth to the Chaldeans — Giving up his vain hopes of safety in the city, and bringing his spirit down to his condition; shall live — God had declared it to be his purpose to give up Judea and the neighbouring countries to the dominion of the Chaldeans: so they who would comply with his declared will should have their lives spared, the rest should be destroyed as fighting against God. And his life shall be unto him for a prey — That is, he shall save his life with as much difficulty and hazard as a prey is taken from the mighty: he shall escape but very narrowly. Or, he shall think himself a considerable gainer by escaping with his life in so general a destruction. For I have set my face against this city — To lay it waste and not to protect it; for evil — Which shall have no good mixed with it, no mitigation, or merciful allay; and, therefore, you have no way of safety, but begging quarter of the Chaldeans, and surrendering yourselves prisoners of war. In vain did Rabshakeh persuade the Jews to do this, while they had God for them, Isaiah 36:16. But it was the best course they could take now, God being against them.

Verse 11-12
Jeremiah 21:11-12. And touching the house of the king of Judah, &c. — The house of Zedekiah, the court, or those who were magistrates. Hear ye the word of the Lord — These, how great soever, are not excused from the common obligations which lie upon all to listen to and obey the revelations of the divine will. Execute judgment in the morning — Do it diligently, do it quickly, and do not delay to do justice upon appeals made to you, and tire out your poor petitioners as you have done. Those magistrates that would fill their places well, and do their duty, must rise early. This is so expressed because it was usual for kings and judges to sit for the administration of justice in a morning. Lest my fury go out like fire — Many commentators have been of opinion that this prophecy, from the 11th verse, belongs to the same subject with chapter 22., and relates to the time of Jehoiakim. And from these words, lest my fury, &c., they infer, that it was antecedent to the prophecy at the beginning of the chapter, and to that peremptory decree published against the king’s house, mentioned Jeremiah 21:7 of this chapter, “But I cannot help thinking,” says Blaney, “that this latter part is but a continuation of the same prophecy with which the chapter begins; for the house of David was still to be visited with more calamities than those which had befallen it in the days of Jehoiakim. And how peremptory soever the decree may sound, (Jeremiah 21:7,) we must remember the rule laid down concerning such decrees, (Jeremiah 18:7-8,) none of which, it seems, are irreversible on the condition of a change of conduct. And, though God may well be supposed to know when no such ground of reversal will take place, yet it is agreeable to the justice of his providence repeatedly to admonish sinners of the means by which his judgments may be avoided, that they may have none to blame but themselves when the threatened vengeance overtakes them.”

Verse 13-14
Jeremiah 21:13-14. Behold, I am against thee, O inhabitant of the valley, and rock of the plain — A description of Jerusalem, which was built in part upon the rocky mountain of Zion, but a great part of it was in the valley; and the higher mountains about mount Zion made that mountain itself, in comparison with them, to appear as a valley. Which say, Who shall come down against us? — They confided in the strength of their situation, as the Jebusites, the ancient inhabitants of the place, had formerly done. “Yet how many times,” says Bishop Newton, “was Jerusalem taken, though it was a very strong place and wonderfully fortified, both by nature and art! It was taken by Shishak king of Egypt, by Nebuchadnezzar, by Antiochus Epiphanes, by Pompey, by Socius, and Herod, before its final destruction by Titus.” I will kindle a fire in the forest thereof — The word forest is often metaphorically taken for a city in the prophetical writings. See Jeremiah 22:7; Ezekiel 20:46; Zechariah 11:1. Or it may mean the forest of Lebanon, or their houses made of wood cut out of that forest, especially those of the royal family, or their idolatrous groves. And it shall devour all things round about it — And this fire shall not end in the destruction of this city, but shall totally destroy all the adjacent country.