Numbers 18:8-10

8The Lord said to Aaron, ‘I give you authority over the things that people offer to me. As priests, part of the gifts that people bring will belong to you and your sons. This rule will always be true for you and your descendants.

9I am giving to you the parts that do not burn on the altar. A part of all these gifts will belong to you: grain offerings, sin offerings and guilt offerings. These are holy gifts and they belong to you and to your sons.

10All the men in your family may eat these gifts. Remember that they are holy gifts.