The posuk in Bamidbar 17:31 says, “As soon as Moshe finished talking to them, the ground opened up and swallowed them.” The kashya is, why didn’t Moshe daven that Korach
There are a number of answers to the above question. The first answer is that Moshe felt weakened since Bnei Yisroel sinned so many times that Moshe lost the ability to daven for them in this world. The second tirutz could be that Moshe was worried that during the time he will be davening for Korach, more of the Bnei Yisroel will be caught up with apikorsus and therefore time was of essence.
The third tirutz is that since Korach was mezalzel in M
The fourth answer is that Moshe had davened to Hash
The last answer could be based on what the Mashgiach of Chevron says in his sefer Ohr Meir. He explains that Moshe Rabbeinu was actually punished because he did not daven that Korach and his eida should do teshuva, The least that Moshe should have davened for was that Korach get a job in the Mishkan. This is based on Gemara Sotah 13b that says: who was greater than Moshe Rabbeinu where Hashem said to him “rav lach”? Hashem refused his tefilla with the word “rav” in response to Moshe saying, ”Rav lachem bnei Levi.” Hashem said to Moshe, you hit them with a stick and with the same stick you will be hit.
May we be zocheh that all of Klal Yisroel do teshuva!
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