Numbers 18:21

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.

Numbers 18:24

18:24 But I have given to the Levites for an inheritance the tithes of the Israelites that are offered to the Lord as a raised offering. That is why I said to them that among the Israelites they are to have no inheritance.”