1 Chronicles 15:23

And Berechiah and Elkanah were doorkeepers for the ark.

The verse stands in the account of David bringing the ark from the house of Obed-edom to Jerusalem and placing it in the tabernacle he had prepared for it there. Berechiah and Elkanah were Levites appointed as doorkeepers to guard the ark during its transport. Their guarding belonged to a wider ordered service in which singers, instrumentalists, and other Levites took part in a worship procession with the ark. Practical duties and music were thus joined together in the service surrounding the ark.