6 And David organized them in divisions corresponding to the sons of Levi: Gershom, Kohath, and Merar'i. 7 The sons of Gersham were Ladan and Shim'e-i. 8 The sons of Ladan: Jehi'el the chief, and Zetham, and Jo'el, three. 9 The sons of Shim'e-i: Shelo'moth, Ha'zi-el, and Haran, three. These were the heads of the fathers' houses of Ladan. 10 And the sons of Shim'e-i: Jahath, Zina, and Je'ush, and Beri'ah. These four were the sons of Shim'e-i. 11 Jahath was the chief, and Zizah the second; but Je'ush and Beri'ah had not many sons, therefore they became a father's house in one reckoning. 12 The sons of Kohath: Amram, Izhar, Hebron, and Uz'ziel, four. 13 The sons of Amram: Aaron and Moses. Aaron was set apart to consecrate the most holy things, that he and his sons for ever should burn incense before the Lord, and minister to him and pronounce blessings in his name for ever.
Matthew Henry's Commentary on 1 Chronicles 23:6-13
Commentary on 1 Chronicles 23:1-23
(Read 1 Chronicles 23:1-23)
David, having given charge concerning the building of the temple, settles the method of the temple service, and orders the officers of it. When those of the same family were employed together, it would engage them to love and assist one another.