Numbers 8:6, 16, 18

“Now set the Levites apart from the rest of the people of Israel and make them ceremonially clean.

“Of all the people of Israel, the Levites are reserved for me. I have claimed them for myself in place of all the firstborn sons of the Israelites; I have taken the Levites as their substitutes.

Yes, I have claimed the Levites in place of all the firstborn sons of Israel.