1 Chronicles 23:31-32

New Revised Standard Version, Anglicised Catholic Edition

³¹ and whenever burnt-offerings are offered to the Lord on sabbaths, new moons, and appointed festivals, according to the number required of them, regularly before the Lord. ³² Thus they shall keep charge of the tent of meeting and the sanctuary, and shall attend the descendants of Aaron, their kindred, for the service of the house of the Lord.’