And the Lord spake unto Moses At the same time he gave the instructions about the consecration of the Levites, the time of their entrance on their service, and of leaving it, was fixed: saying; as follows.
21
The Levites purified themselves and washed their clothes; then Aaron presented them before the Lord as a presentation offering. Aaron also made atonement for them to ceremonially cleanse them.
22
After that, the Levites came to do their work at the tent of meeting in the presence of Aaron and his sons. So they did to them as the Lord had commanded Moses concerning the Levites.