Leviticus 10:10-12

10You must know what is holy. And you must know what is not holy. You must know what you can use. And you must know what you must not use to worship me.

11You must teach Israel's people all the rules that I, the Lord, gave to them by Moses.’

12Moses said to Aaron and to his two other sons Eleazar and Ithamar, ‘The grain offering is most holy. Take the part that you did not burn in front of the Lord. And make it into bread. Do not use yeast. Take it to the side of the altar and eat it.