2 Chronicles 30:16-17

16They stood in their proper places. God's servant Moses had written in God's law where they should stand. The Levites gave the blood from the sacrifices to the priests. The priests then splashed the blood on the altar.

17Many of the people had not made themselves properly clean. So they could not kill their lambs for the Passover and offer them to the Lord. The Levites had to kill the lambs for those people instead.