Numbers:8:14-16
rsv@Numbers:8:14 @ "Thus you shall separate the Levites from among the people of Israel, and the Levites shall be mine.
rsv@Numbers:8:15 @ And after that the Levites shall go in to do service at the tent of meeting, when you have cleansed them and offered them as a wave offering.
rsv@Numbers:8:16 @ For they are wholly given to me from among the people of Israel; instead of all that open the womb, the first-born of all the people of Israel, I have taken them for myself.