The Lord spoke to Moses, saying:
Take the Levites from among the Israelites and cleanse them.
Thus you shall do to them, to cleanse them: sprinkle the water of purification on them, have them shave their whole body with a razor and wash their clothes, and so cleanse themselves.
Then let them take a young bull and its grain offering of choice flour mixed with oil, and you shall take another young bull for a sin offering.
You shall bring the Levites before the tent of meeting, and assemble the whole congregation of the Israelites.
When you bring the Levites before the Lord, the Israelites shall lay their hands on the Levites,
and Aaron shall present the Levites before the Lord as an elevation offering from the Israelites, that they may do the service of the Lord.
The Levites shall lay their hands on the heads of the bulls, and he shall offer the one for a sin offering and the other for a burnt offering to the Lord, to make atonement for the Levites.
Then you shall have the Levites stand before Aaron and his sons, and you shall present them as an elevation offering to the Lord.
Thus you shall separate the Levites from among the other Israelites, and the Levites shall be mine.
Thereafter the Levites may go in to do service at the tent of meeting, once you have cleansed them and presented them as an elevation offering.
For they are unreservedly given to me from among the Israelites; I have taken them for myself, in place of all that open the womb, the firstborn of all the Israelites.
For all the firstborn among the Israelites are mine, both human and animal. On the day that I struck down all the firstborn in the land of Egypt I consecrated them for myself,
but I have taken the Levites in place of all the firstborn among the Israelites.
Moreover, I have given the Levites as a gift to Aaron and his sons from among the Israelites, to do the service for the Israelites at the tent of meeting, and to make atonement for the Israelites, in order that there may be no plague among the Israelites for coming too close to the sanctuary.
Moses and Aaron and the whole congregation of the Israelites did with the Levites accordingly; the Israelites did with the Levites just as the Lord had commanded Moses concerning them.
The Levites purified themselves from sin and washed their clothes; then Aaron presented them as an elevation offering before the Lord, and Aaron made atonement for them to cleanse them.
Thereafter the Levites went in to do their service in the tent of meeting in attendance on Aaron and his sons. As the Lord had commanded Moses concerning the Levites, so they did with them.
The Lord spoke to Moses, saying:
This applies to the Levites: from twenty-five years old and upward they shall begin to do duty in the service of the tent of meeting;
and from the age of fifty years they shall retire from the duty of the service and serve no more.
They may assist their brothers in the tent of meeting in carrying out their duties, but they shall perform no service. Thus you shall do with the Levites in assigning their duties.
New Revised Standard Version Bible, copyright 1989, Division of Christian Education of the National Council of the Churches of Christ in the United States of America. Used by permission. All rights reserved. (New Revised Standard Bible Version Online)