And prepare yourselves according to {your families}, according to your working groups, according to the decree of David king of Israel and according to the decree of Solomon his son. Verse ConceptsWriting

Then Solomon offered burnt offerings to Yahweh on the altar of Yahweh that he had built before the portico, {as was the daily requirement}, to offer up according to the commandments of Moses for Sabbaths, new moon festivals, and the three {annual} feasts: the Feast of Unleavened Bread, the Feast of Weeks, and the Feast of Booths. And in accord with the ordinance of David his father he appointed working groups of priests for their service, Levites for their responsibilities for praise and cultic service before the priests {according to the daily requirement}, and the gatekeepers in their working groups, gate by gate. For thus David the man of God had commanded. read more.
And they did not turn aside from the commandment of the king concerning the priests and the Levites concerning anything, and concerning the treasury rooms. And Solomon accomplished all the work from the day the foundation stone [was laid for] the house of Yahweh until its completion, and the house of Yahweh was finished.

They kept the responsibility of their God and the responsibility of cleansing, and the singers and gatekeepers, according to the command of David and his son Solomon.