1 Chronicles 23:30-32

30They are to stand every morning to thank and to praise the Lord, and likewise at evening,

31and to offer all burnt offerings to the Lord, 1on the Sabbaths, the new moons and 2the appointed festivals, in the number determined by the ordinance concerning them, continually before the Lord.

32So 3they are to perform the 4duties of the tent of meeting, the holy place, and 5of assisting the sons of Aaron their relatives, for the service of the house of the Lord.