Numbers 18:12-15

12I will give to you the best olive oil, the best wine and the best grain. The people give to the Lord the first part of these that they get.

13I also give to you the best parts of the food that people bring to the Lord. Any clean person who lives in your house may eat them.

14Everything in Israel that should belong to me is now yours.

15I give to you every firstborn animal and male child that people offer to the Lord. But you must pay the price for every firstborn son and for every firstborn male animal that is not clean.