1 Chronicles 23:26-29

26And also unto the Levites; they shall no more carry the tabernacle, nor any vessels of it for the service thereof.

27For by the last words of David the Levites were numbered from twenty years old and above:1

28Because their office was to wait on 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 the work of the service of the house of God;2

29Both for the shewbread, and for the fine flour for meat offering, 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;3