Question: I saw that according to the Arizal if one fasts during the aseres yemei teshuva, this could rectify all the sins one did his entire life for each day of the week that corresponds to the day that one fasted.
These days (between Rosh Hashanna and Yom Kippur) correspond to all the days of the week except Shabbat. If I also want to atone for Shabbat, should I fast one more day at some point or was the intention of the Arizal only for the weekdays and not Shabbat?
Answer: The Arizal writes in Pri Etz Chaim (Sha’ar Hashofar Perek 5) “In these days [of the aseres yemei teshuva] one should engage in complete teshuva, because on each day it is possible to achieve forgiveness for all the sins that a person has performed on that day [of the week] his entire life”.