Jeremiah 21

1 Zedekiah had refused to listen to Jeremiah before, but not Jerusalem was under siege as was predicted and Zedekiah was desperate for help.
2 One might think it is a good thing that Zedekiah is now seeking help from God, but notice what is missing from his request. There is no sign of confession or repentance. He had probably made this request to all his idols and when the circumstances did not change he turned to God hoping that He would perform upon request.
4 But God answers Zedekiah harshly. The Babylonians would indeed be victorious in the siege. Judah's own weapons would be used against them (either by the advancing Babylonian army or by infighting among the Jews).
5 But even worse than that, God was against them and defeat them in ways no army could.
9 Even though God had promised to destroy Jerusalem He still has an act of mercy for them. This is their very last chance to obey. If anyone surrenders to the Babylonians he will escape the horrors of the battle that is about to take place in Jerusalem. Anyone who remains in the city only proves their obstinate refusal to listen to God and will seal their fate in the city doomed for destruction.
12 The leaders either were the oppressors or were willing to take bribes. It would not have been in "their" best interest to change.
13 Judah may have had some impressive strongholds, but their overconfidence would not thwart God's judgment against them.