Reuven had much to gain if Yosef were to be out of the picture. He was the firstborn. Yosef was a threat to his position, since he, too, was a firstborn. The shevatim rendered a halachic decision, finding Yosef guilty of being a redifah, a pursuer, who was bent on destroying them. Reuven attempted to dissuade them for one purpose: so that he could return later and release Yosef from the pit, thereby saving his life. Horav Zalman Sorotzkin, zl, observes the incredible level of atzilus, nobility, that was manifest by Reuven’s actions. As far as the shevatim were concerned, either Yosef or Reuven would be the bechor, the aristocrat of the shevatim. Reuven was the only one who would benefit from Yosef’s “displacement,” since he had previously been considered to be the bechor, but, due to his impulsivity, he had lost that status to Yosef.
Nonetheless, Reuven took a position with regard to Yosef. He may no longer have been the bechor, which meant that the firstborn fringe benefits were no longer his. He did not care. As far as he was concerned, however, he was the bechor in assuming responsibility. He knew that a stand had to be taken, and, as the bechor, he should be the responsible party, the one to assume that stand. He may no longer have had firstborn rights, but he still retained firstborn responsibilities, which he could now execute. He could overrule his brothers.
All too often we spend most of our time seeking excuses to validate our lack of participation with regard to helping others. Reuven teaches us that small people avoid responsibility. A true leader does what must be done; he assumes responsibility, no matter the consequences.