Deuteronomy 17:14-15

14“When you come to the land that Adonai your God is giving you, possess it and dwell in it, and you say, ‘I will set a king over me, like all the nations around me,’

15you will indeed set over yourselves a king, whom Adonai your God chooses. One from among your brothers will be appointed as king over you—you may not put a foreigner over you, who is not your brother.