Deuteronomy 17:14-17

“When you enter the land which the LORD your God gives you, and you possess it and live in it, and you say, ‘I will set a king over me like all the nations who are around me,’ you shall surely set a king over you whom the LORD your God chooses, one from among your countrymen you shall set as king over yourselves; you may not put a foreigner over yourselves who is not your countryman. Moreover, he shall not multiply horses for himself, nor shall he cause the people to return to Egypt to multiply horses, since the LORD has said to you, ‘You shall never again return that way.’ He shall not multiply wives for himself, or else his heart will turn away; nor shall he greatly increase silver and gold for himself.