Albert Barnes Commentary Jeremiah 19:3

"and say, Hear ye the word of Jehovah, O kings of Judah, and inhabitants of Jerusalem: thus saith Jehovah of hosts, the God of Israel, Behold, I will bring evil upon this place, which whosoever heareth, his ears shall tingle." — Jeremiah 19:3 (ASV)

Kings - Plural because the message (Jeremiah 19:3–9), related not especially to the reigning king, but to the whole royal house.