Jeremiah 18:18

The Jews were only hardened by the foregoing prophecy, and determined to compass Jeremiah’s death.

Let us devise devices - i. e., “deliberately frame a plot” for his ruin (see Jeremiah 18:11 note).

The law shall not perish ... - As the Law of Moses was imperishable, the people probably drew the conclusion that the Levitical priesthood must also endure forever, and therefore that Jeremiah’s predictions of national ruin were blasphemous (compare Acts 6:13).

Let us smite him with the tongue - Their purpose was to carry a malicious report of what he had said to king Jehoiakim, and so stir up his anger against him.