Question: why is yom kippur fast 25 hours?
Answer: The fast lasts for 25 hours, rather than the typical 24 of a full day. The 25-hour observance on Yom Kippur allows a cushion of time for the subjectivity of “nightfall” as a moment in time, Chabad says. Those familiar with the Jewish faith may know that Shabbat, or the sabbath, lasts for 25 hours, too.