Numbers 18:25-32 - Instructions For The Levites
25 Yahweh spoke to Moses, saying, 26 "You will speak to the Levites and say to them, 'When you receive the tithe from the {Israelites} that I have given to you from them for your inheritance, {you will present} a contribution from it to Yahweh, a tithe from a tithe. 27 Your contribution will be credited to you like the grain from the threshing floor and like the produce from the press. 28 So {you will present} your own contribution to Yahweh from all your tithes that you receive from the {Israelites}; from it you will give the contribution of Yahweh to Aaron the priest. 29 From all your gifts {you will present} every contribution of Yahweh, from all its fat, the part [that is] sacred.'
30 You will say to them, 'When {you are presenting} its fat, the rest will be credited to the Levites like a yield of the threshing floor and like a yield from the press. 31 You may eat it anywhere, you and your household, because it [is] a wage in return for your service in the tent of assembly. 32 You will not bear any sin because {you have presented} its fat; you will not defile the holy objects of the {Israelites}, or you will die.'"