דברי הימים א, פרק ה׳, פסוק ח׳

The ancestral records of the tribe of Reuben serve as more than a simple family tree. They map the physical boundaries of their settlements across the Jordan River, capturing a dynamic history of shifting borders and regional changes. The recorded lineage connects the current generation back to previously established ancestors. Commentators differ on the exact identities of these forebears; some suggest a connection to a figure named Shemaiah [רד״ק], while others identify the ancestor as Shimei, a grandson of Joel [מלבי״ם].

The claim that these descendants settled in the city of Aroer presents a historical puzzle, as earlier records indicate that Aroer was originally built by and belonged to the tribe of Gad. To resolve this, the primary approach among commentators suggests a spatial understanding of the boundary. Rather than living inside the city limits, the people of Reuben may have begun their settlement starting from the edge of Aroer and spreading outward [רד״ק, ביאור שטיינזלץ], or they simply populated the surrounding territories while the city itself remained under the control of Gad [מצודת דוד, רד״ק].

Alternatively, this geographical shift might reflect a later period in history, sometime after the reign of King Saul. As the tribes living east of the Jordan River won military victories and expanded their territories, they had to reorganize their lands. Because the tribe of Reuben was blocked from further eastern expansion by the natural boundary of the Euphrates River, the tribe of Gad transferred control of Aroer to them in order to balance the newly acquired territories [מלבי״ם].

The territorial description further outlines the width of Reuben's land from north to south, extending to the areas of Nebo and Baal Meon [מצודת דוד]. Beyond merely marking geographical coordinates, these locations carry deep cultural significance. In the ancient world, local nations frequently named their cities after their deities, and both Nebo and Baal Meon were originally titles of foreign idols. Upon conquering these regions, the Israelites deliberately changed these city names, actively working to erase the legacy of idol worship from the land [רש״י].