Numbers 18:21, 22, 23, 24

“To the Levites I have given every tithe in Israel for an inheritance, in return for their service that they do, their service in the tent of meeting

so that the people of Israel do not come near the tent of meeting, lest they bear sin and die.

But the Levites shall do the service of the tent of meeting, and they shall bear their iniquity. It shall be a perpetual statute throughout your generations, and among the people of Israel they shall have no inheritance.

For the tithe of the people of Israel, which they present as a contribution to the LORD, I have given to the Levites for an inheritance. Therefore I have said of them that they shall have no inheritance among the people of Israel.”