March 26, 2021, 7:00 am
The sunrise to sunset ta’anit (fast) b’chorim (of the firstborn) is the only fast that applies to just a segment of the community: all males who are the firstborn children in their families (if the firstborn child is female, the first son born after her is not obligated). The father of a child too young to fast fasts for him, and if he himself is bekhor, the mother fasts for the child on the day of Erev Pesach [the day in which Passover begins at nightfall]. Since it is forbidden to abstain from eating on Shabbat except for Yom Kippur), when Erev Pesach falls on Saturday night, the fast takes place on Thursday.
There is a widely practiced exemption: On the principle that fasting is prohibited on a joyous occasion, Judaism allows for anyone who attends a religious feast to forego fasting. It is customary to hold a celebratory meal on the completion of study of a tractate of Talmud, called a siyyum (conclusion). So rabbis initiated the practice of studying a portion of a Talmud tractate after morning services, held especially early on Erev Pesach. All the firstborn are invited to be present for the conclusion and share a seudat (meal) mitzvah (in honor of a commandment; in this case, studying the Torah).