2 Chronicles 29:15-17

15And they gathered their brethren, and sanctified themselves, and went in, according to the commandment of the king by the words of Jehovah, to cleanse the house of Jehovah. 16And the priests went in unto the inner part of the house of Jehovah, to cleanse it, and brought out all the uncleanness that they found in the temple of Jehovah into the court of the house of Jehovah. And the Levites took it, to carry it out abroad to the brook Kidron. 17Now they began on the first day of the first month to sanctify, and on the eighth day of the month came they to the porch of Jehovah; and they sanctified the house of Jehovah in eight days: and on the sixteenth day of the first month they made an end.