1 Kings 18:17-20

18:17 When Ahab saw Elijah, he said to him, “Is it really you, the one who brings disaster on Israel?” 18:18 Elijah replied, “I have not brought disaster on Israel. But you and your father’s dynasty have, by abandoning the Lord’s commandments and following the Baals. 18:19 Now send out messengers and assemble all Israel before me at Mount Carmel, as well as the 450 prophets of Baal and 400 prophets of Asherah whom Jezebel supports.

18:20 Ahab sent messengers to all the Israelites and had the prophets assemble at Mount Carmel.