Deuteronomy 17:18-20

18"And when he sits on the throne of his kingdom, he shall write for himself in a book a copy of this law, approved by the Levitical priests.

19And it shall be with him, and he shall read in it all the days of his life, that he may learn to fear the Lord his God by keeping all the words of this law and these statutes, and doing them,

20that his heart may not be lifted up above his brothers, and that he may not turn aside from the commandment, either to the right hand or to the left, so that he may continue long in his kingdom, he and his children, in Israel.