Numbers 18:19-20

18:19 All the raised offerings of the holy things that the Israelites offer to the Lord, I have given to you, and to your sons and daughters with you, as a perpetual ordinance. It is a covenant of salt forever before the Lord for you and for your descendants with you.”

Duties of the Levites

18:20 The Lord spoke to Aaron, “You will have no inheritance in their land, nor will you have any portion of property among them – I am your portion and your inheritance among the Israelites.