1 Chronicles 23:27-32

27 For by the last words of David, the Levites were numbered from twenty years old and above.
28 And their station was at the hand of the sons of Aaron for the service of the house of the LORD, in the courts, and in the chambers, and in the purifying of all holy things, and in the work of the ministry of the house of God,
29 both for the showbread and for the fine flour for the sacrifice and for the unleavened cakes and for that which is baked in the pan and for that which is fried and for all manner of measure and size,
30 and to stand every morning to thank and praise the LORD, and likewise in the evening;
31 and to offer all burnt sacrifices unto the LORD in the sabbaths, in the new moons and solemnities, by number, according to the order commanded unto them, continually before the LORD.
32 And that they should keep the charge of the tabernacle of the testimony and the charge of the holy place and the charge of the sons of Aaron, their brethren, in the ministry of the house of the LORD.
The Jubilee Bible (from the Scriptures of the Reformation), edited by Russell M. Stendal, Copyright © 2000, 2001, 2010