These divisions of the gatekeepers, corresponding to their leaders, had assigned responsibilities, like their relatives, as they served in the Lord’s temple.

He appointed some of the Levites to serve before the ark of the Lord, to offer prayers, songs of thanks, and hymns to the Lord God of Israel.

David ¹  left Asaph and his colleagues there before the ark of the Lord’s covenant to serve before the ark regularly and fulfill each day’s requirements, ² 

They performed music ¹  before the sanctuary ²  of the meeting tent until Solomon built the Lord’s temple in Jerusalem. ³  They carried out their tasks according to regulations.

Then David said, “Only the Levites may carry the ark of God, for the Lord chose them to carry the ark of the Lord and to serve before him perpetually.

The sons of Amram: Aaron and Moses. Aaron and his descendants were chosen on a permanent basis to consecrate the most holy items, to offer sacrifices before the Lord, to serve him, and to praise his name. ¹ 

What follows is a list of Israelite family leaders and commanders of units of a thousand and a hundred, as well as their officers who served the king in various matters. Each division was assigned to serve for one month during the year; each consisted of 24,000 men. ¹ 

David assembled in Jerusalem ¹  all the officials of Israel, including the commanders of the tribes, the commanders of the army divisions that served the king, the commanders of units of a thousand and a hundred, the officials who were in charge of all the property and livestock of the king and his sons, the eunuchs, and the warriors, including the most skilled of them.