Rashi explains that the juxtaposition of Yehuda’s brothers deposing him and the loss of his wife and two sons upon the story of Yosef (in fact, it is placed right in the middle of the Yosef incident) teaches us that one who commences a mitzvah (Yehudah undertook to save Yosef, but did not complete his mission), but does not complete it, will bury his wife and children. It seems like a harsh punishment. After all, at least he started the mitzvah, while others did not even bother to get involved. Yet, he is punished; they are not. What is even more surprising here is that had Yehudah not intervened, his brothers would have killed Yosef. Apparently, the punishment for commencement without conclusion is greater than for one who did not even commence the mitzvah. Why is this?
Horav Yerucham Levovitz, zl, explains that one who embarks on a mitzvah and does not complete it is compared to one who forfeits his children. In his commentary to the beginning of Parashas Noach, Rashi explains that the primary offspring of the righteous comprise their acts of lovingkindness. Thus, a person should be acutely aware that one who performs an act of lovingkindness creates spiritual merits for himself. Therefore, one who initiates a mitzvah has already earned his merit by virtue of its initiation. He now has a Heavenly z’chus, merit, in his corner. According to Rashi, this is considered as if he has brought a child into the world. Now, if he does not complete the mitzvah, what happens to the z’chus/child? I will leave the reader to fill in the blanks. This is a frightening and quite sobering lesson concerning our avodas ha’kodesh, service to the Almighty. We must learn to acknowledge that the performance of every mitzvah is like giving birth to a child.