Jeremiah 40:15-16

Then Johanan the son of Kareah spake to Gedaliah in Mizpah secretly, saying, Let me go, I pray thee, and I will slay Ishmael the son of Nethaniah, and no man shall know it: wherefore should he slay thee, that all the Jews which are gathered unto thee should be scattered, and the remnant in Judah perish? But Gedaliah the son of Ahikam said unto Johanan the son of Kareah, Thou shalt not do this thing: for thou speakest falsely of Ishmael.