A Warning Not To Listen To The False Prophets Who Are Already Doomed Because Of Their False Prophecies And Equally False Ways (Jeremiah 29:20-23).
“Hear you therefore the word of YHWH, all you of the captivity, whom I have sent away from Jerusalem to Babylon.”
Having explained why what the prophets were declaring was hopelessly wrong, Jeremiah now calls on all who are in captivity, despatched by YHWH from Jerusalem to Babylon, to hear the word of YHWH concerning the prophets themselves.
“Thus says YHWH of hosts, the God of Israel, concerning Ahab the son of Kolaiah, and concerning Zedekiah the son of Maaseiah, who prophesy a lie to you in my name, ‘Behold, I will deliver them into the hand of Nebuchadrezzar king of Babylon, and he will slay them before your eyes, and of them shall be taken up a curse by all the captives of Judah who are in Babylon, saying, YHWH make you like Zedekiah and like Ahab, whom the king of Babylon roasted in the fire, because they have wrought folly in Israel, and have committed adultery with their neighbours' wives, and have spoken words in my name falsely, which I did not command them, and I am he who knows, and am witness, the word of YHWH.”
It would appear that the two named prophets were actively conspiring against Nebuchadrezzar along with other dissidents in Babylon, as well as seeking to arouse the exiles to join in their conspiracy. That would be why they were picked out for special attention. Their names are otherwise unknown to us, but they were clearly known to Nebuchadrezzar. (The change back to Nebuchadrezzar from Nebuchadnezzar (Jeremiah 29:1; Jeremiah 29:3) was because the former was how it was spelled in the letter, an incidental confirmation of the accuracy of the narrative). The fact that Jeremiah knew of them confirms that he was in close touch with what was happening among the exiles, and that regular correspondence went to and fro. Thus he was able to declare what would happen to them when he learned of their activities. YHWH would cause them to be arrested and brought before Nebuchadrezzar and sentenced to burning in a furnace, which was seemingly a regular punishment meted out by Nebuchadrezzar (Daniel 3:11; Daniel 3:15; Daniel 3:20-21). And this would be done before the eyes of the exiles as a warning to them of what happened to those who engaged in treasonable activity.
But the wider reason for the judgment brought on them as far as YHWH was concerned was that they had not only told lies in His Name, but had also ‘wrought folly in Israel', a phrase which regularly indicates adultery and always a gross sin worthy of death (compare Genesis 34:7; Deuteronomy 22:21; Joshua 7:15; Judges 20:6). For they had committed adultery with their neighbours' wives, possibly when being officially consulted by them. As YHWH's prophets this brought deep shame on His Name. And on top of this were the lies that they told in His Name, which He had not commanded. Thus they were doubly worthy of death, and a death so shocking that it would be used as a curse among the Jewish exiles in Babylon in the future. That this occurred we need not doubt. That is why it is recorded.
‘And I am he who knows, and am witness, the word of YHWH.' These words are probably YHWH's although they could be Jeremiah's. For He is the One Who knows all things, and was therefore witness to their transgression. Either way they were a distinct reminder that YHWH knew exactly what was going on in Babylon. They should all be aware that they could not escape from His scrutiny just because they were there and not in Jerusalem.