- A בן סורר ומורה’s time period is three months, בן ולא הראוי לקרותו אב
On the previous Daf, Amoraim disagreed if a קטן can possibly father a child. A Baraisa from Rebbe Yishmael’s yeshivah taught: "בן" ולא אב – only a “son” can become a בן סורר ומורה, but not one who is a father. The Gemara asks, since Rebbe Kruspedai taught: כל ימיו של בן סורר ומורה – the entire period when a boy can become a ben sorer umoreh אינו אלא שלשה חדשים בלבד – is merely three months, how could he be a father during that period? Apparently, a קטן can father a child, and the Baraisa is discussing a woman who conceived from him before he reached adulthood and gave birth during those three months!? The Gemara answers that a קטן cannot father a child, and the case is a woman who conceived after he reached adulthood. Rebbe Yishmael’s derashah is explained: "בן" ולא הראוי לקרותו אב – only a “son” can become a בן סורר ומורה, but not one who is fit to be called a father. Once he is an adult for three months, and a pregnancy from him would be noticeable, he is excluded from the law of בן סורר ומורה.
- We follow רוב even regarding דיני נפשות (ראוי לקרותו אב, contradictory testimony re: the date)
Rav Huna brei d’Rav Yehoshua inferred from Rebbe Kruspedai (that a boy is "ראוי לקרותו אב" after three months of adulthood), that the pregnancy of a woman who gives birth after just seven months (instead of nine), is not noticeable לשליש ימיה – after a third of her days (i.e., two and one-third months), but after three months. Otherwise, a boy should be excluded from בן סורר ומורה in less than three months, since he can impregnate a woman who gives birth after seven months!? Ravina rejected the proof, saying: זיל בתר רובא – follow the majority. Since most women give birth after nine months, he is not ראוי לקרותו אב until after three full months. Rav Huna objected: the Torah instructs Beis Din to attempt to save someone accused of a capital offense ("והצילו העדה"), ואת אמרת זיל בתר רובא – and you say to follow the majority to give capital punishment?! However, Ravina proved that we do, because a Mishnah teaches that if עדים contradict each other if a capital offense occurred on the second or third day of the month, the testimony is valid, because we assume one did not know the previous month was extended. This is because we follow the majority, ורובא דאינשי עבדי דטעו בעיבורא דירחא – and most people err about the extension of months.
- Learning from דורות הראשונים about a קטן fathering a child at age eight
A Baraisa states that a woman whose son performed העראה with her (the first stage of relations), Beis Shammai says: פסלה מן הכהונה – he has disqualified her from the Kehunah (since he is forbidden to her), and Beis Hillel permits her to a Kohen. Rav Chisda said that all agree that a nine-year-old’s relations are halachically considered relations, and he would disqualify her, and all agree that the relations of one younger than eight years old do not disqualify her. They argue about an eight-year-old: Beis Shammai holds גמרינן מדורות הראשונים – we learn from previous generations, whose men fathered children at eight years old, that such relations are relations, but Beis Hillel says we do not learn from previous generations. The Gemara seeks to prove that eight-year-olds of previous generations fathered children. After the first attempts are rejected, the Gemara eventually proves that בצלאל was twenty-six years younger than his great-grandfather כלב. After subtracting two years for the pregnancies of the three generations, it emerges that three generations fathered children over twenty-four years, proving that each generation fathered a child at age eight.
