2 Chronicles 30:15-17

15Then they slaughtered the Passover lambs on the fourteenth day of the second month. And the priests and the Levites were ashamed of themselves, and consecrated themselves and brought burnt offerings to the house of the Lord.

16They stood at their accustomed stations, in accordance with the Law of Moses, the man of God. The priests sprinkled the blood [which they received] from the hand of the Levites [on the altar].

17For there were many in the assembly who had not consecrated themselves [that is, become ceremonially clean and free from all sin]; so the Levites had to slaughter the Passover lambs for everyone who was not clean, in order to make them holy for the Lord.