Numbers 18:24-27

²⁴Because I have given as a distinct portion to the Levites for an inheritance the tithes of the children of Israel, whatever they shall offer to the Lord; therefore I said to them, In the midst of the children of Israel they shall have no inheritance.

²⁵And the Lord spoke to Moses, saying,

²⁶You shall also speak to the Levites, and shall say to them, If you° take the tithe from the children of Israel, which I have given you from them for an inheritance, then shall you° separate from it a heave-offering to the Lord, a tenth of the tenth.

²⁷And your heave-offerings shall be reckoned to you as corn from the floor, and an offering from the wine-press.