Nehemiah 12:45
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.
1 Chronicles 25:1-26
And David and the commanders of the army set apart for the service the sons of Asaph, [of] Heman, and [of] Jeduthun, who prophesied with stringed instruments, with harps, and with cymbals. And their inventory of the men of the work [and] for their duty was:
1 Chronicles 23:28
For their station [was] {to assist} the sons of Aaron with the service of the house of Yahweh, over the courtyards, over the chambers, and over the cleansing of all the sanctified objects, and [with] the work of the service of the house of God,
2 Chronicles 23:6
Let no one enter into the house of Yahweh except the priests and the ministering Levites. They themselves may enter, for they [are] holy, but all the people shall keep the requirements of Yahweh.