במדבר, פרק ג׳, פסוק כ״א

The census of the Levite families requires careful organization to ensure every individual is accurately recorded under their proper ancestral line. When detailing the descendants of Gershon, the narrative repeats the names of his sons, Libni and Shimei, even though they were already identified earlier in the account. The primary approach among commentators is that this repetition does not serve to introduce new genealogical information. Instead, it acts as a necessary transition into the detailed counting of the people. Because the broader narrative leading up to this point is quite lengthy, the text briefly refreshes the memory regarding the specific family names just before presenting their final numbers [מזרחי].

The relationship between Gershon and his descendants is presented in a way that requires careful understanding, as a simple reading might mistakenly imply that Gershon himself belonged to his son's family. To clarify this, the narrative conveys that the counted men of the Libni and Shimei families rightfully belonged to the broader house of Gershon. This clarifies the progression of the account: it first assigns the individuals to Gershon as a single collective, and then transitions to discussing the multiple families and their specific populations [דברי דוד].

Rather than counting each family independently, the census groups them together under the primary name of Gershon. This highlights that the goal of the count is to record the main ancestral branch as a single, unified entity. Nevertheless, explicitly naming the smaller, individual families remains essential. A person could only prove his status as a descendant of Gershon, and thus be included in the census, by tracing his lineage back to one of these well-known, established family lines [גור אריה]. The conclusion of the account confirms that these specific groups were the only families established by Gershon, ensuring there were no other primary branches within his lineage [מלבי״ם].