יהושע, פרק כ״ב, פסוק כ״ה

The tribes of Reuben and Gad harbor a deep fear of being cut off and alienated from the rest of the nation. They explain that the altar they built was never intended for offering sacrifices. Rather, it was constructed to serve as an eternal witness and memorial. It stands to prove that they remain an inseparable part of God's people and His land, even though a river physically divides them [רלב״ג].

Their primary anxiety centers on the generations to come. They worry that the tribes living within the land of Israel will eventually point to the river as a divine boundary line. Over time, those living in the land might look at the tribes across the Jordan and declare that they have no share in God, viewing them simply as residents of a foreign country [ביאור שטיינזלץ].

This geographical divide could lead to a devastating spiritual reality. The fear is that the descendants living in the land of Israel will actively block and prevent the descendants across the river [מצודת ציון] from following and fearing God [מצודת דוד]. This prevention would be carried out through total exclusion, casting them out of the community and treating them as complete strangers who no longer belong to the nation of God [ביאור שטיינזלץ].