Take the Levites instead of all the firstborn among the children of Israel, and the cattle of the Levites instead of their cattle; and the Levites shall be mine: I am the LORD.
Numbers 3:12
And I, behold, I have taken the Levites from among the children of Israel instead of all the firstborn that openeth the matrix among the children of Israel: therefore the Levites shall be mine;
And the LORD said unto Moses, Number all the firstborn of the males of the children of Israel from a month old and upward, and take the number of their names.
And thou shalt take the Levites for me (I am the LORD) instead of all the firstborn among the children of Israel; and the cattle of the Levites instead of all the firstlings among the cattle of the children of Israel.