C. F. Keil and Franz Delitzsch on 1 Kings 22:28

1Ki 22:28

In his consciousness of the divine truth of his announcement, Micah left the king with these words: “If thou come back safe, Jehovah has not spoken by me. Hear it, all ye nations.” עמּים does not mean people, for it is only in the antique language of the Pentateuch that the word has this meaning, but nations; and Micah thereby invokes not only the persons present as witnesses of the truth of his words, but the nations generally, Israel and the surrounding nations, who were to discern the truth of his word from the events which would follow (see at Mic 1:2).