Nehemiah 12:45
And, with the singers and the doorkeepers, they kept the ward of their God, and the ward of the purification, according to the commandment of David and of Solomon his son.
1 Chronicles 25:1-26
And David and the captains of the host separated for the service those of the sons of Asaph and of Heman and of Jeduthun who were to prophesy with harps and lutes and cymbals; and the number of the men employed according to their service was:
1 Chronicles 23:28
For their place was by the side of the sons of Aaron for the service of the house of Jehovah, over the courts, and over the chambers, and over the purifying of all holy things, and for the work of the service of the house of God;
2 Chronicles 23:6
But let none come into the house of Jehovah except the priests and those of the Levites that do the service; they shall go in, for they are holy; but all the people shall keep the watch of Jehovah.