Numbers 18:21-24

21“To the sons of Levi, behold, I have given all the 1tithe in Israel as an inheritance, in return for their service which they perform, the service of the tent of meeting. 22And 2the sons of Israel shall not come near the tent of meeting again, or they will bring sin on themselves and die. 23Only the Levites shall perform the service of the tent of meeting, and they shall 3bear their own guilt; it shall be a permanent statute throughout your generations, and among the sons of Israel 4they shall have no inheritance. 24For the tithe of the sons of Israel, which they offer as an offering to the Lord, I have given to the Levites as an inheritance; therefore I have said concerning them, ‘5They shall have no inheritance among the sons of Israel.’”