Cross reference
Numbers 18:26
26 Moreover you shall speak to the Levites, and tell them, When you take of the children of Israel the tithe which I have given you from them for your inheritance, then you shall offer up a heave-offering of it for Yahweh, a tithe of the tithe.
Nehemiah 10:38
38 The priest the son of Aaron shall be with the Levites, when the Levites take tithes: and the Levites shall bring up the tithe of the tithes to the house of our God, to the chambers, into the treasure-house.
Numbers 18:21
21 To the children of Levi, behold, I have given all the tithe in Israel for an inheritance, in return for their service which they serve, even the service of the tent of meeting.