Fast of the Firstborn
Fast of the Firstborn (Hebrew: תַעֲנִית בְּכוֹרוֹת, romanized: taʿăniṯ bəḵoroṯ or תַעֲנִית בְּכוֹרים taʿăniṯ bəḵorim) is a unique fast day in Judaism, which usually falls on the day before Passover (i.e., 14 Nisan, a month in the Hebrew calendar; Passover begins on 15 Nisan). In modern times, the fast is usually broken at a siyum celebration (typically made after Shaharit), which, according to the prevailing custom, creates an atmosphere of rejoicing that overrides the requirement to continue the fast.