Deuteronomy 4:1-2, 40

“And now, O Israel, listen to the statutes and the rules that I am teaching you, and do them, that you may live, and go in and take possession of the land that the LORD, the God of your fathers, is giving you. You shall not add to the word that I command you, nor take from it, that you may keep the commandments of the LORD your God that I command you.

Therefore you shall keep his statutes and his commandments, which I command you today, that it may go well with you and with your children after you, and that you may prolong your days in the land that the LORD your God is giving you for all time.”