Deuteronomy 18:1-5 NKJV
“The priests, the Levites—all the tribe of Levi—shall have no part nor inheritance with Israel; they shall eat the offerings of the LORD made by fire, and His portion. Therefore they shall have no inheritance among their brethren; the LORD is their inheritance, as He said to them.
“And this shall be the priest’s due from the people, from those who offer a sacrifice, whether it is bull or sheep: they shall give to the priest the shoulder, the cheeks, and the stomach. The firstfruits of your grain and your new wine and your oil, and the first of the fleece of your sheep, you shall give him. For the LORD your God has chosen him out of all your tribes to stand to minister in the name of the LORD, him and his sons forever.
NKJV: New King James Version