Numbers 18:23-24

23The Levites will perform the service of the Tent of Meeting. They will bear the responsibility for their iniquity. It is a permanent ordinance throughout your generations. So among Bnei-Yisrael they are to receive no inheritance.

24For I have given the tithes that Bnei-Yisrael present to Adonai as an offering to the Levites as an inheritance. That is why I said they would receive no inheritance among Bnei-Yisrael.”