Numbers 18:26
"You are to speak to the Levites, and you must tell them, 'When you receive from the Israelites the tithe that I have given you from them as your inheritance, then you are to offer up from it as a raised offering to the Lord a tenth of the tithe.
Nehemiah 10:38
A priest of Aaron's line will be with the Levites when the Levites collect the tithes, and the Levites will bring up a tenth of the tithes to the temple of our God, to the storerooms of the treasury.
Numbers 18:21
See, I have given the Levites all the tithes in Israel for an inheritance, for their service which they perform -- the service of the tent of meeting.