Nehemiah 12:45
They performed the service of their God and the service of purification, along with the singers and gatekeepers, according to the commandment of David and his son Solomon.
1 Chronicles 25:1-26
David and the army officers selected some of the sons of Asaph, Heman, and Jeduthun to prophesy as they played stringed instruments and cymbals. The following men were assigned this responsibility:
1 Chronicles 23:28
Their job was to help Aaron's descendants in the service of the Lord's temple. They were to take care of the courtyards, the rooms, ceremonial purification of all holy items, and other jobs related to the service of God's temple.
2 Chronicles 23:6
No one must enter the Lord's temple except the priests and Levites who are on duty. They may enter because they are ceremonially pure. All the others should carry out their assigned service to the Lord.