Deuteronomy 13:5

13:5 As for that prophet or dreamer, he must be executed because he encouraged rebellion against the Lord your God who brought you from the land of Egypt, redeeming you from that place of slavery, and because he has tried to entice you from the way the Lord your God has commanded you to go. In this way you must purge out evil from within.

Deuteronomy 13:9

13:9 Instead, you must kill him without fail! Your own hand must be the first to strike him, and then the hands of the whole community.