1 Kings 22:10-12

10And the king of Israel and Jehoshaphat the king of Judah sat each on his throne, having put on their robes, in an open place in the entrance of the gate of Samaria; and all the prophets prophesied before them.1

11And Zedekiah the son of Chenaanah made him horns of iron: and he said, Thus saith Yhwh, With these shalt thou push the Syrians, until thou have consumed them.

12And all the prophets prophesied so, saying, Go up to Ramoth–gilead, and prosper: for Yhwh shall deliver it into the king’s hand.