Numbers 8:1-8:14
The Lord spoke to Moses, saying: Speak to Aaron and say to him, "When you mount the lamps, let the seven lamps give light at the front of the lampstand." Aaron did so; he mounted the lamps at the front of the lampstand, as the Lord had commanded Moses.-- Now this is how the lampstand was made: it was hammered work of gold, hammered from base to petal. According to the pattern that the Lord had shown Moses, so was the lampstand made.
The Lord spoke to Moses, saying: Take the Levites from among the Israelites and cleanse them. This is what you shall do to them to cleanse them: sprinkle on them water of purification, and let them go over their whole body with a razor, and wash their clothes; thus they shall be cleansed. Let them take a bull of the herd, and with it a meal offering of choice flour with oil mixed in, and you take a second bull of the herd for a sin offering. You shall bring the Levites forward before the Tent of Meeting. Assemble the whole Israelite community, and bring the Levites forward before the Lord. Let the Israelites lay their hands upon the Levites, and let Aaron designate the Levites before the Lord as an elevation offering from the Israelites, that they may perform the service of the Lord.
The Levites shall now lay their hands upon the heads of the bulls; one shall be offered to the Lord as a sin offering and the other as a burnt offering, to make expiation for the Levites.
You shall place the Levites in attendance upon Aaron and his sons, and designate them as an elevation offering to the Lord. Thus you shall set the Levites apart from the Israelites, and the Levites shall be Mine.