Neither must the children of Israel henceforth come nigh the tabernacle of the congregation, lest they bear sin, and die.(Numbers 18:22)

But the Levites shall do the service of the tabernacle of the congregation, and they shall bear their iniquity: it shall be a statute for ever throughout your generations, that among the children of Israel they have no inheritance.(Numbers 18:23)

But the tithes of the children of Israel, which they offer as an heave offering unto the LORD, I have given to the Levites to inherit: therefore I have said unto them, Among the children of Israel they shall have no inheritance.(Numbers 18:24)

Thus speak unto the Levites, and say unto them, When ye take of the children of Israel the tithes which I have given you from them for your inheritance, then ye shall offer up an heave offering of it for the LORD, even a tenth part of the tithe.(Numbers 18:26)

And this your heave offering shall be reckoned unto you, as though it were the corn of the threshingfloor, and as the fulness of the winepress.(Numbers 18:27)

Thus ye also shall offer an heave offering unto the LORD of all your tithes, which ye receive of the children of Israel; and ye shall give thereof the LORD's heave offering to Aaron the priest.(Numbers 18:28)