Numbers 18:26
Thus speak to the Levites, and say to them, When you take of the children of Israel the tithes which I have given you from them for your inheritance, then you shall offer up an heave offering of it for the LORD, even a tenth part of the tithe.
Nave's Topical Index—AKJV

Nehemiah 10:38
And 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.
Nave's Topical Index—AKJV