Deuteronomy 17:8, 18

“If a matter arises which is too hard for you to judge, between degrees of guilt for bloodshed, between one judgment or another, or between one punishment or another, matters of controversy within your gates, then you shall arise and go up to the place which the LORD your God chooses.

“Also it shall be, when he sits on the throne of his kingdom, that he shall write for himself a copy of this law in a book, from the one before the priests, the Levites.