Leviticus 6:16-18

16What is left of it Aaron and his sons are to eat. It shall be eaten as unleavened bread in a holy place; they are to eat it in the courtyard of the Tent of Meeting.

17It shall not be baked with leaven [which represents corruption or sin]. I have given it as their share of My offerings by fire; it is most holy, like the sin offering and the guilt offering.

18Every male among the sons of Aaron may eat it [as his share]; it is a permanent ordinance throughout your generations, from offerings by fire to the Lord. Whatever touches them will become consecrated (ceremonially clean).’ ”