Numbers 18:22-24

22The Israelites shall never again approach the Tent of Meeting [the covered sanctuary, the Holy Place, and the Holy of Holies], or they [who do] will incur sin and die.

23Only the Levites shall perform the service of the Tent of Meeting (tabernacle), and they shall bear their iniquity; it shall be a statute forever throughout your generations, that the Levites shall have no inheritance [of land] among the children of Israel.

24But the tithe of the Israelites, which they present as an offering to the Lord, I have given to the Levites as an inheritance; therefore I have said to them, ‘They shall have no inheritance among the children of Israel.’ ”