Deuteronomy 17:11

17:11 You must do what you are instructed, and the verdict they pronounce to you, without fail. Do not deviate right or left from what they tell you.

Deuteronomy 17:20

17:20 Then he will not exalt himself above his fellow citizens or turn from the commandments to the right or left, and he and his descendants will enjoy many years ruling over his kingdom in Israel.