Rabbi Shmuel Herzfeld remembers the Yom Kippur of his childhood surrounded by the mournful cries of his fellow worshippers, so it is not surprising that he grew up with an image of Yom Kippur as a purely solemn day. Yet his book emphasizes a different aspect of Yom Kippur, the most important holiday of the Jewish faith: it is not a day of mourning, but a day of celebrating. According to the Talmud, it is the happiest day of the Jewish year. This book explains why Yom Kippur is such a joyous day, and explores the implications of this approach to the holiday as it relates to our entire religious experience.