Numbers 18:25

21 Behold, I have given to the Levites all the tithes in Israel as an inheritance in return for the work they do, the service of the Tent of Meeting.

22 No longer may the Israelites come near to the Tent of Meeting, or they will incur guilt and die.

23 The Levites are to perform the work of the Tent of Meeting, and they must bear their iniquity. This is a permanent statute for the generations to come. The Levites will not receive an inheritance among the Israelites.

24 For I have given to the Levites as their inheritance the tithe that the Israelites present to the LORD as a contribution. That is why I told them that they would not receive an inheritance among the Israelites.”

25 And the LORD instructed Moses,

26 “Speak to the Levites and tell them: ‘When you receive from the Israelites the tithe that I have given you as your inheritance, you must present part of it as an offering to the LORD—a tithe of the tithe.

27 Your offering will be reckoned to you as grain from the threshing floor or juice from the winepress.

28 So you are to present an offering to the LORD from all the tithes you receive from the Israelites, and from these you are to give the LORD’s offering to Aaron the priest.

29 You must present the offering due the LORD from all the best of every gift, the holiest part of it.’

Read all of Numbers 18