Yom Kippur, the Jewish Day of Atonement, is considered the most sacred day on the Jewish calendar and is marked by fasting and prayer. This year, the holiday begins at sundown on October 3 and ends on the evening of October 4.
In this picture, ultra-Orthodox Jews in Israel perform the Kaparot ceremony, in which sins are symbolically transferred to a chicken. The animal is then slaughtered and given to charity.
—By Jane J. Lee, photo gallery by Mallory Benedict