“Then they said.
‘Come!
Let us make plots against Jeremiah!
Instruction shall not perish
From the priest.
Counsel shall not perish
From the wise.
The word shall not perish
From the prophet.
Come!
Let us bring charges against him!
Let us not heed any of his words!’”
This unidentified they, maybe the people of Anathoth mentioned in chapter 11, are making a plot against Jeremiah. This is Jeremiah reporting about a plot against himself. These people said, that if they got rid of Jeremiah, the priests would still instruct, the wise would still counsel people, and the prophets would still prophesize. Thus they decided to bring charges against him. They were not going to listen to his words anymore.