Numbers 8:20

“And Moses and Aaron, and all the congregation of the children of Israel, etc.] The several parties concerned in the consecration of the Levites: these did to the Levites according unto all that the Lord commanded Moses, so did the children of Israel unto them: which, as Jarchi notes, is said to the praise of them that did it, and of what was done by them; everything was done that was ordered, and in the manner in which it was prescribed; Moses sprinkled, or ordered to be sprinkled, the water of purification on them, and set them before the tabernacle, and before the Lord; the children of Israel laid their hands on them, and Aaron waved them, offered the sacrifices for them.”

“The Levites could only undertake their duties Numbers 3:0; Numbers 4:0 after the formal exchange of the Levites for the first-born Numbers 3:44-51. The distinction between the “consecration” of the priests Leviticus 8:0 and the less solemn “purification” Numbers 8:21 of the Levites is marked. These rites of purification are similar to those incumbent on the priests of Egypt. Numbers 8:7 Water of purifying - literally, “sin water:” i. e. water to cleanse from sin; no doubt taken from the laver of the sanctuary, which was used by the priests for purification before they went into the tabernacle to minister (compare Numbers 5:17; Exodus 30:18 ff). The “sprinkling” of so large a body of men…”

“Num 8:20-22 contain an account of the execution of the divine command. Numbers 8:23”