II Chronicles 30:13-17

Now many people, a very great assembly, gathered at Jerusalem to keep the Feast of Unleavened Bread in the second month. They arose and took away the altars that were in Jerusalem, and they took away all the incense altars and cast them into the Brook Kidron. Then they slaughtered the Passover lambs on the fourteenth day of the second month. The priests and the Levites were ashamed, and sanctified themselves, and brought the burnt offerings to the house of the LORD. They stood in their place according to their custom, according to the Law of Moses the man of God; the priests sprinkled the blood received from the hand of the Levites. For there were many in the assembly who had not sanctified themselves; therefore the Levites had charge of the slaughter of the Passover lambs for everyone who was not clean, to sanctify them to the LORD.