לזכות החברותא שלי באורות התשובה הר"ר אהרן ישראל בן משה מרדכי שליט"א וכל בני ביתו!!
The days of teshuva are WONDERFUL. They give us the opportunity to clean our slate and start anew. The mazel [astrological sign] of Elul is בתולה! This means we are new and fresh. Then comes Rosh Hashana - a BRAND NEW YEAR! Then Yom Kippur where the very day itself atones ["עיצומו של יום מכפר"].
But there is a price that we pay. All of this emphasis we place on constricting and contracting our will in order to avoid sin also affects our positive will. To be happy means to be expansive. The word for happy is שמחה which relates to צמיחה - sprouting and growth. A person is happy when he feels that his abilities and potential are being actualized. When a person is holding himself back this inhibits simcha. On Yom Kippur we fast. To fast in Hebrew is לצום. The word in Hebrew for "contraction" is צמצום. It is a "double צם". Super contraction. To afflict oneself is certainly an act of self contraction and instead of sprouting we literally become less [מיעוט חלב ודם].
So again - we are SOOOO HAPPY for this "cleansing diet" of teshuva to the point of not eating on Yom Kippur. But there is a psychological price we pay. There is a weakening of the will. This is forbidden and that is forbidden, don't say this and don't say that. This affects our desire to do good because we are being put a little bit in the corner.
The antidote is ... SUCCOSSSS!!!!! AHHHHHHH!! The holiday of gathering "חג האסיף". We eat drink, sing and dance. Our fruits and vegetables which sprouted are brought into the house. We take the four species which also sprouted. We decorate our Succah to make it beautiful and we attempt to experience the GREATEST SIMCHA OF THE YEAR [according to halacha - ושמחת בחגך is only said explicitly about Succos] - even greater than PURIM:-).
Now we have everything! The teshuva and selicha of the days of Elul, Rosh Hashana and Yom Kippur in addition to the expansion of ourselves with the simcha of Sukkos. Now the teshuva, return to Hashem is complete.
In the words of the Rav ztz"l in Oros Ha-tshuva [9-10]:
כשמקמצים את עז הרצון, כשכופפים את עז החיים, ע"י הסלידה הפנימית, והנטייה לשוב מכל חטא, מתקמץ ג"כ הרצון של הטוב, עז החיים הטהורים מתחלש גם הוא. נמצא האדם סובל מטהרתו המוסרית חולשה כזאת, שסובל חולה שהתרפא ע"י הזרמה אלקטרית, שאמנם גרשה את הארס שבמחלתו, אבל החלישה את הכוח החי והבריא שבו.
שבים, ע"כ באים ימים של שמחת קדש, של חדות נפש, לקומם את הרצון הטוב ועז החיים הטהור. אז תהיה התשובה שלמה" (אורות התשובה ט, י ).