Exod. 29:28 These things shall be a perpetual ordinance for Aaron and his sons from the Israelites, for this is an offering; and it shall be an offering by the Israelites from their sacrifice of offerings of well-being, their offering to the Lord.
Exod. 34:15 You shall not make a covenant with the inhabitants of the land, for when they prostitute themselves to their gods and sacrifice to their gods, someone among them will invite you, and you will eat of the sacrifice.