2 Chronicles 29:29-34

29 Then King Hezekiah and all the people knelt down and worshiped God.
30 The king and the leaders of the nation told the Levites to sing to the Lord the songs of praise that were written by David and by Asaph the prophet. So everyone sang with great joy as they knelt and worshiped God.
31 Hezekiah said to the people, "Now that you are ritually clean, bring sacrifices as offerings of thanksgiving to the Lord." They obeyed, and some of them also voluntarily brought animals to be sacrificed as burnt offerings.
32 They brought 70 bulls, 100 sheep, and 200 lambs as burnt offerings for the Lord;
33 they also brought 600 bulls and 3,000 sheep as sacrifices for the people to eat.
34 Since there were not enough priests to kill all these animals, the Levites helped them until the work was finished. By then more priests had made themselves ritually clean. (The Levites were more faithful in keeping ritually clean than the priests were.)