The great Talmudic sage, Rabbi Akiva, was taken captive by the Romans on Tishrei 5 of the year 3894 from creation (134 CE). His subsequent torture and execution is recalled in the stirring Eleh Ezkarah poem of the Yom Kippur service.
The Shabbat between Rosh Hashanah and Yom Kippur is called Shabbat Shuvah, "Shabbat of Return." The name derives from the Haftarah (reading from the prophets) for this Shabbat, which opens with the words (Hosea 14:2), "Return O Israel unto the L-rd your G-d..." Occurring in the "Ten Days of Repentance" (see "Laws & Customs" for Tishrei 3), it is a most auspicious time to rectify the failings and missed opportunities of the past and positively influence the coming year.
The master Kabbalist Rabbi Isaac Luria ("Ari") taught that the seven days between Rosh Hashanah and Yom Kippur (which will always include one Sunday, one Monday, etc.) correspond to the seven days of the week. The Sunday between Rosh Hashanah and Yom Kippur includes within itself all Sundays of the year; the Monday embodies all Mondays, and so on. Shabbat Shuvah is thus the archetypal Shabbat -- the juncture in time at which we are empowered to influence every Shabbat of our year.
The 10-day period beginning on Rosh Hashanah and ending on Yom Kippur is known as the "Ten Days of Repentance"; this is the period, say the sages, of which the prophet speaks when he proclaims (Isaiah 55:6) "Seek G-d when He is to be found; call on Him when He is near." Psalm 130, Avinu Malkeinu and other special inserts and additions are included in our daily prayers during these days.
The Baal Shem Tov instituted the custom of reciting three additional chapters of Psalms each day, from the 1st of Elul until Yom Kippur (on Yom Kippur the remaining 36 chapters are recited, thereby completing the entire book of Psalms). Click below for today's three Psalms.
Chapter 100 Chapter 101 Chapter 102
Links: About the Ten Days of teshuvah; Voicemail; more on teshuvah
When his people broke the deal and incurred divine wrath by worshipping a calf of gold, Moses told G‑d:
“Forgive them. And if You do not, erase me from Your book that You have written.”
Meaning:
“I know You want to forgive them. You love them no matter what. You loved them before, when they had all but abandoned You in Egypt. And You love them now as well.”
“What has occurred since then? That you have given them your Torah. So that it’s only this book, your Torah, that stands in the way.”
“And if so, I want no part in such a book.”
This was the response for which G-d was waiting, for which He chose Moses to begin with. So it was that then, through Moses, G‑d wrote forgiveness into His book.
And so must we.