1 Chronicles 15:9 (KJV)

And David assembled the children of Aaron, and the Levites:

Of the sons of Kohath; Uriel the chief, and his brethren an hundred and twenty:

Of the sons of Merari; Asaiah the chief, and his brethren two hundred and twenty:

Of the sons of Gershom; Joel the chief and his brethren an hundred and thirty:

Of the sons of Elizaphan; Shemaiah the chief, and his brethren two hundred:

Of the sons of Uzziel; Amminadab the chief, and his brethren an hundred and twelve.

And David called for Zadok and Abiathar the priests, and for the Levites, for Uriel, Asaiah, and Joel, Shemaiah, and Eliel, and Amminadab,

And said unto them, Ye are the chief of the fathers of the Levites: sanctify yourselves, both ye and your brethren, that ye may bring up the ark of the LORD God of Israel unto the place that I have prepared for it.

For because ye did it not at the first, the LORD our God made a breach upon us, for that we sought him not after the due order.

So the priests and the Levites sanctified themselves to bring up the ark of the LORD God of Israel.