Deuteronomy 17:14-18

14When thou comest unto the land which Jehovah thy 1God giveth thee, and shalt possess it, and shalt dwell therein, and shalt say, I will set a king over me, like all the nations that are about me;

15thou shalt only set him king over thee whom Jehovah thy 2God will choose: from among thy brethren shalt thou set a king over thee; thou mayest not set a foreigner over thee, who is not thy brother.

16Only he shall not multiply horses to himself, nor lead back the people to Egypt, to multiply horses; for Jehovah hath said unto you, Ye shall not return again any more that way.

17Neither shall he multiply wives to himself, that his heart turn not away; neither shall he greatly multiply to himself silver and gold.

18And it shall be, when he sitteth upon the throne of his kingdom, that he shall write for himself a copy of this law in a book out of that which is before the priests, the Levites;