And he appointed, according to the order of David his father, the courses of the priests to their service, and the Levites to their charges, to praise and minister before the priests, as the duty of every day required: the porters also by their courses at every gate: for so had David the man of God commanded.
He set up, just like David his dad planned, the priest's duties and the Levites' jobs, to help and praise before the priests. This was based on what the man of God, David, instructed. He also organized gatekeepers in shifts for each entrance, following David's command.