Gaebelein's Annotated Bible
And the LORD spake unto Moses, saying,6. The Consecration of the Levites
1. The lighting of the candlestick (Numbers 8:1-4)
2. The consecration of the Levites (Numbers 8:5-22)
3. The charge to the Levites repeated (Numbers 8:23-26)
The candlestick is the type of Christ as in the sanctuary, that is, Christ in glory. The lighting of the seven lamps introduced in the beginning of the wilderness book is of blessed meaning. The seven lamps were to illuminate the candlestick of beaten gold, throw their light upon the candlestick so that the gold and beautiful workmanship might be seen. The oil in the seven lamps represents the Holy Spirit. Spiritually applied we have the picture here of the Spirit of God shedding light upon Christ. For this He is given to His people, to glorify Christ. And this is the great need of the people of God in their journey through the wilderness. The eyes of the pilgrim and stranger, the passenger passing through the wilderness, must be fixed upon Christ in glory.
The consecration of the Levites consisted in sprinkling with water, shaving the whole body, washing of their clothes. They had to stand before the tabernacle of the congregation and the whole assembly of the children of Israel was gathered together. The children of Israel had to put their hands upon the Levites. The whole congregation became thus identified with the service of the Levites. The Levites represented the entire congregation of Israel and served in their behalf. The sprinkling with water in their consecration stands typically for the purification from sins. This they could not do for themselves, another had to do it. But the sharp razor they were able to take to remove from their bodies all the hair, which stands for that which belongs to the flesh, the old nature. They had also to wash their clothes, which typically signifies the water (the Word) applied to our habits and to our ways. The lessons are many. He who would be a true Levite in service must constantly use the sharp knife of self-judgment to remove all what is of self.
Their period of service was fixed. It was uniform, from 25 to 50 years. It was a gracious provision that at 50 the Levite was permitted to retire from the harder work. There is no clash here with the statement of chapter 4. From 25 to 30 they could do the lighter work of the tabernacle, even as the Levites over 50 years were exempt from the harder tasks. The Lord still fixes the period in which His servants are to serve Him, as He also looks out for their comfort (John 21:12, Joh_21:18-19).