A researcher of MiDRASH, a project dedicated to analyzing the National Library of Israel’s digital database of all known Hebrew manuscripts using Machine Learning, including manuscripts from the Cairo Geniza, holds up a 12th century fragment of a Yom Kippur liturgy in Jerusalem, Nov. 24, 2025. Photo: REUTERS/Ronen Zvulun

Here are some facts you might not know about the holiday of Yom Kippur, which begins on Sunday evening: 

Yom Kippur is observed on the 10th day of the Jewish month of Tishrei.  It is referred to as a Super Sabbath (Shabbat Shabbaton in Hebrew), concluding 10 soul-searching days, personal and collective accountability, spiritual self-awareness and self-enhancement, beginning on Rosh Hashanah, the first day of the Jewish year.

Ten has a special significance in Jewish tradition: God’s abbreviation is the 10th Hebrew letter (Yod – י); the 10 Commandments; the 10 Plagues of Egypt; Yom Kippur on the 10th day of Tishrei; the 10 spheres of the spiritual universe, highlighting the Biblical Creation; 10 reasons for blowing the Shofar (ram’s horn) on Rosh Hashanah and Yom Kippur; the 10% Biblical gift to God (tithe); Abraham passed 10 divine tests; and many more.

According to Leviticus 23:26-32: “The Lord said to Moses, that the tenth day of this seventh month [Tishrei] is the Day of Atonement …. Do not do any work on that day…. This is a lasting ordinance for generations to come….”

Yom Kippur highlights second-chance-eligibility and renewal through repentance, commemorating the day of divine forgiveness for the sin of worshipping the golden calf idol, and the introduction of the Moses-made second set of the Two Tablets (Ten Commandments). Mankind is urged to learn from mistakes, and refrain from the recurring human fallibility: the temptation to sacrifice spiritual values on the altar of convenience.

The Hebrew word Kippur [כיפור] means atonement/repentance – a derivative of the Biblical word Kaporet [כפורת], which was the dome/cover of the Holy Ark in the Sanctuary, and the word Kopher [כופר], which was the cover/dome of Noah’s Ark and the Holy Altar in the Jerusalem Temple.

Fasting is a key feature of Yom Kippur, reducing material pleasure in order to focus on one’s soul-searching, and enhancing empathy with the needy. The Hebrew spelling of fasting [צומ] is the root of the Hebrew word ((צמצומ for reducing and the Hebrew word for a camera’s focus (צמצמ).

However, Judaism opposes asceticism and self-torment, and therefore views genuine repentance as a critical engine of elevating individuals from despair to hope, from abuse to caring, from intolerance to tolerance, from violence to comity, from isolation to integration, from ignorance to knowledge, and from forgetfulness to commemoration.

There are six annual Jewish fasting days, with Yom Kippur being the most prominent.

Yom Kippur is concluded by blowing the Shofar, which represents a moral wakeup-call, optimism, determination, and peace-through-strength (the peaceful ram deters enemies through its horns). The blowing of the Shofar commemorates the saving of Isaac by a ram; the receipt of the (second) Tablets/Ten Commandments at Mount Sinai (even the sin of the Golden Calf does not foreclose restoration); the re-entry to the Land of Israel and the conquest of Jericho by Joshua; as well as Gideon’s victory over the much larger Midianite military. The Hebrew word Shofar שופר]] means “to enhance,” “top quality,” glory and spiritual pleasure [שפר, שופרא].

The author is a commentator and former Israeli ambassador.