Leviticus 10:10-12

10and that ye may make a distinction between the holy and the common, and between the unclean and the clean; 11and that ye may teach the children of Israel all the statutes which Jehovah hath spoken unto them by Moses.

12And Moses spake unto Aaron, and unto Eleazar and unto Ithamar, his sons that were left, Take the meal-offering that remaineth of the offerings of Jehovah made by fire, and eat it without leaven beside the altar; for it is most holy;