Rashi explains that the tribe of Reuven should not have been counted among the census of the other brothers. Reuven is the only tribe for whom no material, spiritual or moral distinction is mentioned. The only exception is Shimon, who is not mentioned at all. The other tribes, however, are characterized by either their spiritual or moral activity or by their socio-economic status. Reuven, regrettably, had a distinction in neither the spiritual nor the material spheres, having lost his superior position as the firstborn.
The tribe of Reuven was constantly exposed to attacks by its gentile neighbors on the east side of the Jordan. Bearing all of this in mind, one would think that the tribe of Reuven was relegated to a difficult future. Indeed, as Horav S.R. Hirsch, z.l., observes, Reuven represents the “poshut’e Yid,” the average Jew who has one possession equal to all the others — the Torah.
The Torah is the only real treasure of our nation. All Jews are accorded equal possession of it. By blessing the tribe of Reuven together with the other tribes, Moshe indicated that Judaism would not be subjected to elitism. The average Jew, who has no unique distinguishing superiority, still contributes to the eternity of our people. Reuven will live on and not die. To paraphrase Horav Eli Munk, z.l., “No part of Am Yisrael can disappear without permanent damage being done to the entire nation!”