Numbers 18:26
"Tell the descendants of Levi that when they receive tithes from the Israelis (the tithes that I've given you from them as an inheritance), you are to offer a tenth of it as a raised offering for the LORD.
Nehemiah 10:38
"And the priest, the descendant of Aaron, will be with the descendants of Levi when the descendants of Levi receive tithes, and the descendants of Levi will bring the tithe of the tithes into the store rooms of the Temple of our God.
Numbers 18:21
As to the descendants of Levi, certainly I've given all the tithes in Israel as their inheritance in return for their services that they perform at the Tent of Meeting.