Deuteronomy 18:3-5

New Century Version

³ When you offer a bull or sheep as a sacrifice, you must share with the priests, giving them the shoulder, the cheeks, and the inner organs. ⁴ Give them the first of your grain, new wine, and oil, as well as the first wool you cut from your sheep. ⁵ The Lord your God has chosen the priests and their descendants out of all your tribes to stand and serve the Lord always.