Numbers 18:21-24

As for the tribe of Levi, your relatives, I will compensate them for their service in the Tabernacle. Instead of an allotment of land, I will give them the tithes from the entire land of Israel. “From now on, no Israelites except priests or Levites may approach the Tabernacle. If they come too near, they will be judged guilty and will die. Only the Levites may serve at the Tabernacle, and they will be held responsible for any offenses against it. This is a permanent law for you, to be observed from generation to generation. The Levites will receive no allotment of land among the Israelites, because I have given them the Israelites’ tithes, which have been presented as sacred offerings to the LORD. This will be the Levites’ share. That is why I said they would receive no allotment of land among the Israelites.”