Yom Kippur means "Day of Atonement" and refers to the annual Jewish observance of fasting, prayer and repentance. Part of the High Holidays, which also includes Rosh HaShanah (the Jewish New Year), Yom Kippur is considered the holiest day on the Jewish calendar.
Yom Kippur is the moment in Jewish time when we dedicate our mind, body, and soul to reconciliation with our fellow human beings, ourselves, and God. As the New Year begins, we commit to making changes in ourselves after this time of self-reflection. We are commanded to turn to those whom we have wronged first, acknowledging our sins and the pain we might have caused. At the same time, we must be willing to forgive – to let go of certain offenses and the feelings of resentment they provoked in us. On this journey, we are both seekers and givers of pardon. Only then can we turn to God and ask for forgiveness. As we read in the Yom Kippur liturgy, “And for all these, God of forgiveness, forgive us, pardon us, and grant us atonement.”
In three separate passages in the Torah, the Jewish people are told, "the tenth day of the seventh month is the Day of Atonement. It shall be a sacred occasion for you: You shall practice self-denial" (Leviticus 23:27). There are five categories of physical needs from which we customarily abstain on Yom Kippur, of which fasting (not eating or drinking) is the most familiar. This self-denial enables us to put aside our physical desires to concentrate on our spiritual needs through prayer, repentance, and self-improvement.