Charles Ellicott Commentary 1 Chronicles 6:16-19

"The sons of Levi: Gershom, Kohath, and Merari. And these are the names of the sons of Gershom: Libni and Shimei. And the sons of Kohath were Amram, and Izhar, and Hebron, and Uzziel. The sons of Merari: Mahli and Mushi. And these are the families of the Levites according to their fathers` [houses]." — 1 Chronicles 6:16-19 (ASV)

The three branches of Levi with their main subdivisions. Parallel passages, Exodus 6:16–19; Numbers 3:17–20.

Gershom. —See Note on 1 Chronicles 6:1. In the Pentateuch, Gershom is son of Moses; Gershon, son of Levi.

And these are the families of the Levites according to their fathers. —The word 'families' (Hebrew, mishpehuth) does not mean single households, but groups of households, or clans. The sentence concludes the short list of the great Levitical houses, just as at Exodus 6:19. (See also Numbers 3:20, where a like formula appears to introduce what follows.)