1 Chronicles 23:28-29

The duty of the Levites was to help Aaron’s descendants in the service of the temple of the LORD: to be in charge of the courtyards, the side rooms, the purification of all sacred things and the performance of other duties at the house of God. They were in charge of the bread set out on the table, the special flour for the grain offerings, the thin loaves made without yeast, the baking and the mixing, and all measurements of quantity and size.