2 Chronicles 29:12-17

Then the Levites arose, Mahath the son of Amasai, and Joel the son of Azariah, of the sons of the Kohathites; and of the sons of Merari, Kish the son of Abdi, and Azariah the son of Jehallelel; and of the Gershonites, Joah the son of Zimmah, and Eden the son of Joah; and of the sons of Elizaphan, Shimri and Jeuel; and of the sons of Asaph, Zechariah and Mattaniah; and of the sons of Heman, Jehuel and Shimei; and of the sons of Jeduthun, Shemaiah and Uzziel. They gathered their brothers and consecrated themselves and went in as the king had commanded, by the words of the LORD, to cleanse the house of the LORD. The priests went into the inner part of the house of the LORD to cleanse it, and they brought out all the uncleanness that they found in the temple of the LORD into the court of the house of the LORD. And the Levites took it and carried it out to the brook Kidron. They began to consecrate on the first day of the first month, and on the eighth day of the month they came to the vestibule of the LORD. Then for eight days they consecrated the house of the LORD, and on the sixteenth day of the first month they finished.