The text of this pasuk is redundant, since it mentions the deaths of Nadav and Avihu twice in the same pasuk. Daas Zekeinim m’Baalei Tosfos explain that the Torah mentions death twice, since they left no offspring to continue their legacy. For reasons of their own, they did not marry. Thus, it is considered as if they died twice: once when they left this world; and again because they left no one to carry on the memory of their lives and achievements. Horav Zev Weinberger, zl, cites the Talmud Moed Kattan (24a), “When they told Rabbi Yochanan that Rabbi Chaninah had passed away, he rent thirteen expensive wool garments on account of him. He said, ‘The man of whom I was in fear is gone.’” (This part of the Talmud’s questioning Shmuel’s statement that kriyah, rending garments as a display of grief, is only explicable at the time of the most intense grief. Apparently, Rabbi Yochanan did not concur with Shmuel.) The Talmud replies that sages are different, since their teachings are mentioned all the time. Every time they are recalled, it evokes the time of most intense grief, as the loss of their death is once again renewed.
We derive from here that, when a Rebbe or a great sage leaves this world, his passing leaves a void vis-à-vis the Torah that he imparted to his many students. This idea is similar to the Sefas Emes’s question concerning the Torah’s enjoinment to mourn the deaths of Nadav and Avihu (Parashas Shemini; Vayikra 10:6), V’acheichem kol Bais Yisrael yivku es ha’sreifah asher saraf Hashem, “All the house of Yisrael shall bewail the conflagration that Hashem wrought.” The word yivku, shall bewail, is written in the future tense when it should have been written in the present. Much has been posited concerning the idea that the death of a scholar, a Torah leader who inspired many, is different from the void left by one whose life and endeavor did not impact a wide range of people. Every day, every blatt Gemorah, every halachah, sets the stage for noticing the loss of a Rebbe. The void left by his passing is palpable. We feel orphaned, alone and adrift to confront the challenges of life without the captain who had been navigating our journey through the turbulent waters. Every epoch in time, every juncture, renews the grieving of their loss. The deaths of Nadav and Avihu left their mark, not only on the present, but also on generations to come.
When we consider the spiritual impact of the Holocaust in terms of the thousands of gedolei Yisrael that were murdered, this idea takes on a new reality. While, indeed, Torah study in America and Eretz Yisrael has reached impressive numbers, can we imagine what Jewish life would have been had Churban Europe not occurred? The yeshivos, the Roshei Yeshivah, the Rabbanim and the thousands of kehillos kedoshos that were slaughtered would have changed our lives and raised the banner of Torah exponentially. We can truly say that death came twice: their murder, and our continued loss.