1 Chronicles 23:2-32

At the same time he brought together all the leaders of Israel, the priests, and the Levites. The Levites thirty years and older were counted; the total was thirty-eight thousand. David sorted them into work groups: “Twenty-four thousand are in charge of administering worship in the sanctuary; six thousand are officials and judges; four thousand are security guards; and four thousand are to serve in the orchestra, praising GOD with instruments that I have provided for praise.” David then divided the Levites into groupings named after the sons of Levi: Gershon, Kohath, and Merari. The Gershonites: Ladan and Shimei. The three sons of Ladan: Jehiel, Zetham, and Joel. The three sons of Shimei: Shelomoth, Haziel, and Haran, all heads of the families of Ladan. The four sons of Shimei: Jahath, Ziza, Jeush, and Beriah. Jahath came first, followed by Ziza. Jeush and Beriah did not have many sons so they were counted as one family with one task. The four sons of Kohath: Amram, Izhar, Hebron, and Uzziel. The sons of Amram: Aaron and Moses. Aaron was especially ordained to work in the Holy of Holies, to burn incense before GOD, to serve God and bless his Name always. This was a permanent appointment for Aaron and his sons. Moses and his sons were counted in the tribe of Levi. The sons of Moses: Gershom and Eliezer. Shubael was the first son of Gershom. Rehabiah was the first and only son of Eliezer; but though Eliezer had no other sons, Rehabiah had many sons. Shelomith was the first son of Izhar. Hebron had four sons: Jeriah, Amariah, Jahaziel, and Jekameam. Uzziel had two sons: Micah and Isshiah. The sons of Merari: Mahli and Mushi. The sons of Mahli: Eleazar and Kish. Eleazar died without any sons, only daughters. Their cousins, the sons of Kish, married the daughters. Mushi had three sons: Mahli, Eder, and Jerimoth. These are the sons of Levi twenty years and older, divided up according to families and heads of families and listed in the work groups that took care of the worship in the sanctuary of GOD. David said, “Now that the GOD of Israel has given rest to his people and made Jerusalem his permanent home, the Levites no longer have to carry the Tabernacle and all the furniture required for the work of worship.” These last words of David referred only to Levites twenty years old and above. From now on the assigned work of the Levites was to assist Aaron’s sons in the work of worship in GOD’s house: maintain courtyards and closets, keep the furniture and utensils of worship clean, take care of any extra work needed in the work of worship, and provide bread for the table and flour for the Meal Offerings and the unraised wafers—all baking and mixing, all measuring and weighing. Also they were to be present for morning prayers, thanking and praising GOD, for evening prayers, and at the service of Whole-Burnt-Offerings to GOD on Sabbath, at New Moons, and at all festivals. They were on regular duty to serve GOD according to their assignment and the required number. In short, the Levites, with the sons of Aaron as their companions in the ministry of holy worship, were responsible for everything that had to do with worship: the place and times and ordering of worship.