27. On the basis of David's final instructions all Levites were registered for service when they reached the age of twenty,
28. and were assigned the following duties: to help the priests descended from Aaron with the temple worship, to take care of its courtyards and its rooms, and to keep undefiled everything that is sacred;
29. to be responsible for the bread offered to God, the flour used in offerings, the wafers made without yeast, the baked offerings, and the flour mixed with olive oil; to weigh and measure the temple offerings;
30. and to praise and glorify the Lord every morning and every evening