korach and the lesson of rosh chodesh

The gemara (B"B 74a) among the aggadic stories of Rabbah bar bar Channa recounts the following episode that relates to events in our parsha: 

אָמַר לִי: תָּא אַחְוֵי לָךְ בְּלוּעֵי דְקֹרַח. חֲזַאי תְּרֵי בִּיזְעֵי, וַהֲווֹ קָא מַפְּקִי קוּטְרָא. שְׁקַל גְּבָבָא דְעַמְרָא וְאַמְשִׁינֵּהּ בְּמַיָּא, וְדַעֲצִיתֵהּ בְּרֵאשֵׁהּ דְּרוּמְחָא וְעַיְּילֵיהּ הָתָם, וְכִי אַפֵּיק, הֲוָה אִיחֲרַךְ אִיחֲרוֹכֵי. אָמַר לִי: אַצֵּית מַאי שָׁמְעַתְּ, וּשְׁמַעִית דַּהֲווֹ אָמְרִין: ״מֹשֶׁה וְתוֹרָתוֹ אֱמֶת, וְהֵן בַּדָּאִין״. אֲמַר לִי: כֹּל תְּלָתִין יוֹמֵי מַהְדַּר לְהוּ גֵּיהִנָּם לְהָכָא כְּבָשָׂר בְּקַלַּחַת, וְאָמְרִי הָכִי: ״מֹשֶׁה וְתוֹרָתוֹ אֱמֶת, וְהֵן בַּדָּאִין״. 

Sefaria's translation (from Steinsaltz):

Rabba bar bar Ḥana continues his account. The Arab also said to me: Come, I will show you those who were swallowed by the earth due to the sin of Korah. I saw two rifts in the ground that were issuing smoke. The Arab took a shearing of wool, and dipped it in water, and inserted it on the head of a spear, and placed it in there. And when he removed the wool, it was scorched. He said to me: Listen to what you hear; and I heard that they were saying: Moses and his Torah are true, and they, i.e., we in the earth, are liars. The Arab further said to me: Every thirty days Gehenna returns them to here, like meat in a pot that is moved around by the boiling water as it cooks. And every time they say this: Moses and his Torah are true, and they, i.e., we in the earth, are liars.

Rashbam comments: כל תלתין יומין - כל ראש חדש

It seems from Rashbam that this is not some random 30 day cycle, but it is rosh chodesh in particular that brings those who were swallowed by the earth in Korach's rebellion back to the place where they sinned, where they again recant and admit that Moshe is true and that they are liars.  R' Nachman has a hesber why this should be true (Likutei Moharan 10:9), but since understanding R' Nachman is beyond me, let me offer two other suggestions.

Rav Soloveitchik in one of the yahrzeit derashos develops the idea that beis din serves two functions: sometimes B"D acts on their own authority and power, and sometimes B"D acts as representatives of Klal Yisrael, as reflecting the will of the people as a whole.  The Rambam in Sefer haMitzvos sees kiddush hachodesh as reflecting the power of B"D in this second role.  The Rambam writes that there must always be a Jewish presence in Eretz Yisrael because the will of the tzibur of Klal Yisrael means the tzibur in Eretz Yisrael.  B"D that enacts the calendar are just the representatives of this community.

The tragic mistake of Korach is in thinking that the power of the community to create law based on their decisions has no bounds.  The din by kiddush hachodesh is אתם אפילו שוגגין אתם אפילו מזידין אתם אפילו מוטעין.  Even if B"D, as representative of the community, errs, their decision is binding.  Their will, which is the will of the people, is absolute.  

Every Rosh Chodesh the followers of Korach revisit their error. אתם אפילו שוגגין אתם אפילו מזידין אתם אפילו מוטעין works for mistakes made within the framework of halacha, but not to uprooting the system completely.

I saw a different hesber that is based on a yesod of the Maharal.  The korban chatas in the musaf of rosh chodesh in unique in that the Torah describes it as   וּשְׂעִ֨יר עִזִּ֥ים אֶחָ֛ד לְחַטָּ֖את לַה׳.  Why the extra word  לַה׳?  Rashi quotes from Chazal ומדרשו באגדה: אמר הקב״ה: הביאו כפרה עלי שמיעטתי את הירח.  Rashi here is alluding to the Midrash he quotes in Braishis (1:16).  The Torah describes the creation of the sun and the moon as שְׁנֵ֥י הַמְּאֹרֹ֖ת הַגְּדֹלִ֑ים, equal in size.  However, the moon complained that you can't have two kings sharing one crown, and as a result, Hashem knocked it down in size, as Rashi there comments, שוים נבראו, ונתמעטה הלבנה על ידי שקיטרגה ואמרה: אי איפשר לשני מלכים שישתמשו בכתר אחד.  The Midrash Rabbah there comments:

אָמַר רַבִּי פִּינְחָס בְּכָל הַקָּרְבָּנוֹת כְּתִיב שְׂעִיר עִזִּים אֶחָד חַטָּאת, וּבְרֹאשׁ חֹדֶשׁ כְּתִיב (במדבר כ״ח:ט״ו): שְׂעִיר עִזִּים אֶחָד חַטָּאת לַה׳, אָמַר הַקָּדוֹשׁ בָּרוּךְ הוּא הָבִיאוּ כַּפָּרָה עָלַי שֶׁמִּעַטְתִּי אֶת הַיָּרֵחַ, שֶׁאֲנִי הוּא שֶׁגָּרַמְתִּי לוֹ לְהִכָּנֵס בִּתְחוּמוֹ שֶׁל חֲבֵרוֹ, וּמָה אִם זֶה שֶׁנִּכְנַס בִּרְשׁוּת כָּךְ פְּגָמוֹ הַכָּתוּב, הַנִּכְנָס שֶׁלֹא בִּרְשׁוּת עַל אַחַת כַּמָּה וְכַמָּה. רַבִּי לֵוִי בְּשֵׁם רַבִּי יוֹסֵי בַּר אִלְּעָאי אָמַר, דֶּרֶךְ אֶרֶץ הוּא שֶׁיְהֵא הַגָּדוֹל מוֹנֶה לַגָּדוֹל, וְהַקָּטָן מוֹנֶה לַקָּטָן. עֵשָׂו מוֹנֶה לַחַמָּה, שֶׁהִיא גְּדוֹלָה, וְיַעֲקֹב מוֹנֶה לַלְּבָנָה, שֶׁהִיא קְטַנָּה.

אָמַר רַב נַחְמָן וְהוּא סִימָן טַב, עֵשָׂו מוֹנֶה לַחַמָּה שֶׁהִיא גְּדוֹלָה, מַה חַמָּה הַזֹּאת שׁוֹלֶטֶת בַּיּוֹם וְאֵינָה שׁוֹלֶטֶת בַּלַּיְלָה, כָּךְ עֵשָׂו יֵשׁ לוֹ חֵלֶק בָּעוֹלָם הַזֶּה וְאֵין לוֹ חֵלֶק לָעוֹלָם הַבָּא. יַעֲקֹב מוֹנֶה לַלְּבָנָה שֶׁהִיא קְטַנָה, מַה הַלְּבָנָה הַזּוֹ שׁוֹלֶטֶת בַּלַּיְלָה וּבַיּוֹם, כָּךְ יַעֲקֹב יֵשׁ לוֹ חֵלֶק בָּעוֹלָם הַזֶּה וְלָעוֹלָם הַבָּא. רַב נַחְמָן אָמַר כָּל זְמַן שֶׁאוֹרוֹ שֶׁל גָּדוֹל קַיָּם אֵין אוֹרוֹ שֶׁל קָטָן מִתְפַּרְסֵם, שָׁקַע אוֹרוֹ שֶׁל גָּדוֹל, מִתְפַּרְסֵם אוֹרוֹ שֶׁל קָטָן. כָּךְ כָּל זְמַן שֶׁאוֹרוֹ שֶׁל עֵשָׂו קַיָּם אֵין אוֹרוֹ שֶׁל יַעֲקֹב מִתְפַּרְסֵם, שָׁקַע אוֹרוֹ שֶׁל עֵשָׂו מִתְפַּרְסֵם אוֹרוֹ שֶׁל יַעֲקֹב, הֲדָא הוּא דִּכְתִיב (ישעיהו ס׳:א׳-ב׳): קוּמִי אוֹרִי כִּי בָא אוֹרֵךְ. כִּי הִנֵּה הַחשֶׁךְ יְכַסֶּה אֶרֶץ וגו׳.

Many years ago there was a certain Rosh Yeshiva that visited the community we were living in and on Friday night they had an oneg Q/A session where you could ask anything you wanted to the R"Y.  Someone chose this topic to ask about.  What does it mean that Hashem needs a korban as a kaparah for himself?  Does Hashem sin?  Does Hashem need to offer korbanos?  Who is He offering them to?  This R"Y was a big Brisker style lamdan, but this was not his cup of tea, and he told the guy that he has no idea what it means.  The guy then pressed and asked what he is supposed to tell his little kid who asked about this Rashi and thinks that his Tatte should have all the answers, to which the R"Y responded that the kid will now learn his Tatte doesn't know everything.  That too is an important lesson even if it doesn't explain the Rashi.  Brisker lomdus may not help you here, but the Maharal will (Be'er haGolah ch 4 among other places, and see the Ishbitzer in Mei HaShiloach as well in parshas Pinchas).  

Maharal explains that the idea behind a korban, from the root קרב, is to draw closer.  The moon was made smaller in physical size by Hashem, and was left wanting.  Hashem therefore said that in order to make it up to the moon, he will offer a korban, i.e. he will draw the moon closer to Him.  Hashem dwells among the humble and the small.  

We find the same idea by mattan Torah.  Of all the great mountains available, Hashem chose to give the Torah davka on Sinai, the smallest of the lot.  

That's what Chazal mean when they say that Hashem asked for a kapparah.  The korban, the drawing closer of the moon, is the kapparah, is the answer to the complaint of the moon, because what it lost in physical size was more than made up for by its gain in spiritual greatness.  

What Chazal are telling us is that Korach did not absorb the lesson of Rosh Chodesh.  The sun appears to be much bigger than the moon, which is why Eisav reckons the calendar according to the sun -- the biggest and brightest.  Korach too, was attracted to the trappings of the office of kohen gadol.  With such a position comes wealth and authority and respect, all the greatness olam ha'zeh has to offer.  All the talk about kedusha was just posturing, just a sales pitch.

We follow the moon, because we know that external appearances aren't everything; we know that the meausure of "bigness" in olam ha'zeh's yardstick is not accurate -- there is "bigness" in spiritual greatness too.  Every Rosh Chodesh the followers of Korach come back and proclaim this truth, and acknowledge that ״מֹשֶׁה וְתוֹרָתוֹ אֱמֶת, וְהֵן בַּדָּאִין