Bible Commentaries
Numbers 18

Verses 1-32

Support of priests and Levites (18:1-32)

In view of the recent rebellion, God gave further instruction concerning the separate responsibilities of priests and Levites. The Levites were to help the priests and were under their direction, but they were not to do any priestly work in the sanctuary (i.e. the tabernacle-tent). Only the priests could enter the sanctuary, and in so doing they took the risks on behalf of the people for any wrongdoing in relation to God’s holy dwelling (18:1-7).
Since the priests had no time to earn a living like others, they had to be supported in other ways. Their food supplies - meat, oil, wine, grain, fruit, etc. - came partly from offerings that required a portion to be set aside for the priests, and partly from firstfruits and other offerings given to the tabernacle (8-14). When the firstborn of all living things were offered to God, they became, in part, the property of the priests, God’s representatives. When people or animals were redeemed, the priests received the payment (the redemption price). When a firstborn animal was sacrificed, the priest received a portion. The contributions from all these offerings helped compensate the priests for not being allowed to own land (15-20).
Details are then given for the support of the Levites. Like the priests they did religious service for the people, on whose behalf they ran the risk of doing wrong in matters relating to the tabernacle and its ceremonies. In return for this they received the people’s tithes. This constant income from the tithes was also compensation for their not receiving a separate tribal area in Canaan (21-24).
Having received tithes, the Levites themselves then paid tithes. Though the tithe of their income was the produce of other people’s fields and vineyards, God accepted it as being their own. Likewise what remained was reckoned to be their own, and they were free to use it accordingly. The tithes of the Levites helped support the priests (25-32).