Numbers 8:7-9

Amplified Bible

⁷ This is what you shall do to them to [ceremonially] cleanse them: sprinkle the water of purification on them, and let them use a razor over their whole body and wash their clothes, and they will be clean.^{(A) 8} Then let them take a young bull and its grain offering of fine flour mixed with oil, and you shall take another young bull as a sin offering. ⁹ You shall present the Levites before the Tent of Meeting (tabernacle), and you shall also assemble the whole congregation of the children of Israel,