Numbers 8:16-18

Amplified Bible

¹⁶ for they are wholly given to Me from among the Israelites. I have taken them for Myself instead of ^[a]all who are born first, the firstborn of all the Israelites. ¹⁷ For all the firstborn among the Israelites are Mine, among the men and among the animals; on the day that I struck down every firstborn in the land of Egypt, I sanctified and set the Israelites apart for Myself. ¹⁸ And I have taken the Levites instead of every firstborn among the Israelites.