What Is Yom Kippur and How Is It Celebrated? A Brief Explanation of the Day of Atonement

Hanukkah might be the best-known Jewish holiday to gentiles and non-Jews because it's close to Christmas, with Passover a close second because it's loosely tied to Easter. But if someone isn't Jewish, they could possibly go through their whole lives without knowing the significance of one of the most important Jewish holidays, Yom Kippur.

So, what is Yom Kippur's origin story?

Yom Kippur, also known as the Jewish Day of Atonement, is the holiest day of the year for the Jewish faith and is marked each year with a reflection of one's sins, fasting and prayer.

It signals the end of the 10 days of repentance, which begins after Rosh Hashanah, the Jewish New Year. It's a period of time when people observing the holiday reflect on their sins and transgressions of the past year and ask for forgiveness.

Because Yom Kippur is a somber holiday, it's not customary to wish someone a "happy Yom Kippur." For those who have friends observing the holiday and who want to acknowledge the holy day, it's better to wish them a good, easy or meaningful fast, which is done from sundown to sundown on Yom Kippur.

The holiday is connected to the story of Moses and the Exodus from Egypt, the period of time when God freed the Jews from slavery. After God freed the Jews from the slavery they endured in Egypt, they sinned by worshipping a golden calf. Moses, who was on Mount Sinai to learn the laws from God, known as the Ten Commandments, returned to his people with the tablets they were carved on. When Moses saw the golden calf, he became enraged and burned the idol his people turned to in his absence. He then returned to the top of the mountain to ask forgiveness from God.

Moses received that forgiveness on the 10th day of Tishrei, the seventh month of the Jewish calendar, and descended from the mountain. From then on, the 10th day of Tishrei has been known as Yom Kippur.

For nearly 26 hours from sundown Tuesday until sundown Wednesday, Jews observing the holiday will abstain from food and drink, as a means of self-deprivation and compassion. Some people may not even brush their teeth, wash or bathe because the acts involve water.

what is yom kippur and how celebrate
A young Jewish boy blows the shofar horn along the beach in the coastal city of Ashdod, during the ritual of Tashlich on September 29, 2011. Tashlich precedes Yom Kippur, the Jewish Day of Atonement, which will begin on Tuesday evening and conclude on Wednesday at sundown. JACK GUEZ/AFP/Getty

Not everyone is required to fast, though, and anyone who must eat for a medical reason should not abstain from food, according to Chabad, an Orthodox Jewish Hasidic movement. Those who could have their health damaged, even in the long run, from not eating or drinking are exempted and children under the age of nine are also not required to fast. People who believe they will have adverse consequences from fasting may even consult their rabbi ahead of Yom Kippur for advice.

Yom Kippur is largely spent in synagogue, where there are five prayer services, identified by Chabad as Maariv, Shacharit, Musaf, Minchah and Neilah. Maariv, which includes the Kol Nidrei, is the only service to take place on the eve of Yom Kippur.

The morning of Yom Kippur starts with Shacharit and concludes with the Neilah service, which includes a shofar blast, signaling the end of the fast.

Although Yom Kippur is a serious holiday, it's also spent enjoying the company of family and friends. After services—which is often an exciting time because a meal is imminent—people return home or venture to a friend's or family's home to break the fast together.

The menu varies household to household, but it's customary to serve bagels and other dishes prepared ahead of the fast, including tuna or egg salad, noodle kugel or quiche.

Some schools close on Yom Kippur, although it's not required, and some businesses may close. However, some employees are expected to be in the office although work is technically forbidden on Yom Kippur.

While Yom Kippur is a time to reflect on the sins of last year, it's not all gloom and doom. It is also a reminder that God grants redemption.