Numbers 18:26-28

26“Moreover, you shall speak and say to the Levites, ‘When you take from the people of Israel the tithe that I have given you from them for your inheritance, then you shall present a contribution from it to the Lord aa tithe of the tithe. 27 bAnd your contribution shall be counted to you as though it were the grain of the threshing floor, and as the fullness of the winepress. 28So you shall also present a contribution to the Lord from all your tithes, which you receive from the people of Israel. And from it you shall give the Lord’s contribution to Aaron the priest.
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