1 Chronicles 23:24
These were the sons of Levi after the house of their fathers; even the chief of the fathers, as they were counted by number of names by their polls, that did the work for the service of the house of the LORD, from the age of twenty years and upward.
The verse belongs to the account of David's arrangements for the worship of God and his preparation for the temple that Solomon would build. That account falls in the prosperous years of David's reign in 1 Chronicles 21-23, presented as the closing portion. In another arrangement it falls within 1 Chronicles 21-25. The verse records the sons of Levi after the house of their fathers, even the chief of the fathers, as counted by number of names by their polls, that did the work for the service of the house of the Lord. It shows that hereditary records were needed after the exile so that temple service could be carried out by those whose family duty it was.
After the temple was built the Levites were given the work of waiting on the priests in the sanctuary service, preparing the showbread, often leading the singing, collecting the tithe, and doing a large amount of work connected with the service of the Lord. Their work was largely confined to the court. In David's time their sanctuary service began at the age of twenty. At fifty they ceased arduous duties while still retaining charge of the work. Their work typified the work of the gospel ministry of the present day.