Numbers 8:15-16

New International Version

¹⁵ “After you have purified the Levites and presented them as a wave offering,^(A) they are to come to do their work at the tent of meeting.^{(B) 16} They are the Israelites who are to be given wholly to me. I have taken them as my own in place of the firstborn,^(C) the first male offspring^(D) from every Israelite woman.