Fast of the Firstborn
273 Fast of the Firstborn
The custom is that male firstborns fast on Erev Pesach. This includes someone who is a firstborn only to his father or to his mother, or is the first living child that is born after a miscarriage. A firstborn born by Cesarean section does not have to fast. A father who has a firstborn boy should fast for him until his Bar Mitzvah, after which the son fasts for himself. If the father himself is a firstborn, his fast is only for himself and his son’s mother should fast on her son’s behalf until his Bar Mitzvah, unless it is difficult for her.
In today’s day and age, the common custom is that we hear a siyum and fast only until that point. If a person is machmir, strict, and wishes to fast, tavo alav brachah, a blessing should come upon him; however, the common custom is that we participate in a siyum instead. Once a person participates in a siyum, it substitutes the need for fasting. Even a siyum on Mishnayos, a minor siyum, is considered a siyum for this purpose. In the case of a mother who is fasting on her son’s behalf, since in today’s day and age we hear a siyum, she should also do so.
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