Numbers 18:20-23

20And the LORD spoke to Aaron, Thou shalt have no inheritance in their land, neither shalt thou have any part among them: I am thy part and thy inheritance among the children of Israel. 21And, behold, I have given the children of Levi all the tenth in Israel for an inheritance, for their service which they serve, even the service of the tabernacle of the congregation. 22Neither must the children of Israel henceforth come near the tabernacle of the congregation, lest they bear sin, and die.1 23But the Levites shall do the service of the tabernacle of the congregation, and they shall bear their iniquity: it shall be a statute for ever throughout your generations, that among the children of Israel they have no inheritance.