“After that, the Levites shall go in to do the service of the Tent of Meeting.
You shall cleanse them, and offer them as a wave offering.
For they are wholly given to me from among the children of Israel; instead of all who open the womb, even the firstborn of all the children of Israel, I have taken them to me.
For all the firstborn among the children of Israel are mine, both man and animal.
On the day that I struck all the firstborn in the land of Egypt, I sanctified them for myself.