דברי הימים א, פרק ה׳, פסוק ז׳

The historical records of the tribe of Reuben provide a clear view of its leadership hierarchy and the prominent heads of its families. The broader tribal family encompassed all the fellow members of the tribe [ביאור שטיינזלץ]. However, this close-knit group was more specifically centered on the personal friends and associates of the previously mentioned prince, Beerah [מצודת דוד]. Even though Beerah held the formal title of prince, his associates were highly respected in their own right and served as independent heads of their respective families [רד״ק].

The actual effort to document these families by generation took place during the reigns of King Jeroboam and King Jotham [מלבי״ם]. What is presented here is only a partial glimpse into Reuben's lineage, as the complete and primary genealogical registry was kept in the official historical chronicles of the kings of Israel [רש״י].

Through the process of organizing these generational records, a distinct leadership structure became clear. Jeiel was recognized as the senior leader of the tribe, with Zechariah serving immediately below him as the second most important figure [מצודת דוד, רד״ק, ביאור שטיינזלץ]. This top ranking was granted to them because their ancestors were considered more distinguished and honorable than the ancestors of others within the tribe [מצודת דוד]. Furthermore, Jeiel and Zechariah served as the final link in this chain, bringing the entire genealogical registry to its formal conclusion [רש״י].