Yom Kippur, the Day of Atonement, is the holiest day in Judaism. It occurs every year on the 10th day of Tishrei, the seventh month of the Hebrew calendar. Tishrei refers to new beginnings. This year, Yom Kippur begins before sunset on October 4th and ends after nightfall on October 5th. According to tradition, it is on this day that God decides each person’s fate, so Jews are encouraged to make amends and ask for forgiveness for sins committed in the past year. https://www.chabad.org/library/article_cdo/aid/177886/jewish/What-Is-Yom-Kippur.htm
It is believed that the celebration of Yom Kippur arose after the Israelites fled from Egypt and arrived at Mount Sinai where God gave Moses the Ten Commandments. Descending from the mountain, Moses caught his people worshipping a golden calf and broke the tablets in anger. The Israelites atoned for their idolatry and God forgave their sins. https://www.history.com/topics/holidays/yom-kippur-history
The intention of this day is to be self-reflective, focusing on the soul rather than the physical body. For this reason, tradition suggests that people fast, refraining from food and fluids for the full 25 hours of the holiday. It is also part of the tradition to give up what might be considered earthly pleasures such as bathing, wearing makeup or wearing leather shoes, something seen as a luxury in ancient times. https://www.ajc.org/news/what-is-yom-kippur-and-how-is-it-celebrated.
Traditions include a pre-Yom Kippur feast with family and friends that must be finished before sunset to prepare for the next 25 hours of fasting. After the last Yom Kippur service, people gather for a feast of favourite traditional foods. It is customary for religious Jews to wear white as a symbol of purity. Some people make donations or volunteer their time in the days leading up to Yom Kippur to atone and seek forgiveness.
In addition to being a day of private introspection, it is also a day focused on connection within the community. By facing wrongdoing as a collective, it suggests that Jews can overcome obstacles in their path. Yom Kippur is not considered a sad day but a time to wipe the slate clean and to feel hopeful in anticipation of a new beginning.