"Speak thus to the Levites, and say to them: "When you take from the children of Israel the tithes which I have given you from them as your inheritance, then you shall offer up a heave offering of it to the LORD, a tenth of the tithe.
Numbers 18:26
Surrounding context
18:25 Then the LORD spoke to Moses, saying,
18:26 "Speak thus to the Levites, and say to them: "When you take from the children of Israel the tithes which I have given you from them as your inheritance, then you shall offer up a heave offering of it to the LORD, a tenth of the tithe.
18:27 And your heave offering shall be reckoned to you as though it were the grain of the threshing floor and as the fullness of the winepress.