2 Chronicles 29:32

³⁰And King Hezekiah and the princes told the Levites to sing hymns to the Lord in the words of David, and of Asaph the prophet: and they sang hymns with gladness, and fell down and worshiped.

³¹Then Hezekiah answered and said, Now ye have consecrated yourselves to the Lord, bring near and offer sacrifices of praise in the house of the Lord. And the congregation brought sacrifices and thank offerings into the house of the Lord; and every one who was ready in his heart brought whole burnt offerings.

— 2 Chronicles 29:32 —

³³And the consecrated calves were six hundred, and the sheep three thousand.

³⁴But the priests were few, and could not flay the whole burnt offering, so their brethren the Levites helped them, until the work was finished, and until the priests had purified themselves: for the Levites more zealously purified themselves than the priests.