Bechoros 17a

בכורות י״ז ע״א

Bekhorot 17a

Learn Bechoros 17a step by step: Aramaic beside English, every question, answer and proof colour-coded.

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Topic

צאן ברזל generations, an animal that looks like a different species from its mother (בכורה, קרבנות, wool and wine), and twin male firstborns

Overview

The amud opens by finishing the argument between רב הונא and רב יהודה about how many generations of צאן ברזל animals are exempt from בכורה. Each side reads רבן שמעון בן גמליאל's 'even ten generations' and the wording of the משנה so that it fits his own view. Next the גמרא turns to a ewe that gave birth to a goat-like animal. רב אושעיא brings a ברייתא in which רבי מאיר says such an animal is obligated and חכמים say it is exempt. The גמרא tests what 'obligated' could mean and then explains the argument through several possible cases, including רב אשי's case of an animal with only some of its mother's features. רבי יוחנן adds that even רבי מאיר requires the ראש חודש goat to be born from a goat, and the גמרא shows that both פסוקים about such animals are needed. Several אמוראים then compare wool to linen, which does not change, to rule that wool from such an animal is excluded from שעטנז, תכלת and נגעים. רב אשי extends the idea to wine from a vine grown over a fig tree. Finally a new משנה begins: twin male lambs born at the same moment, with opinions of רבי יוסי הגלילי, חכמים, רבי טרפון and רבי עקיבא.

Opening lines

The steps (29)

1. ProofThe words of רבן שמעון בן גמליאל fit רב יהודה
2. ChallengeHow does רב הונא explain 'even ten generations'?
3. Resolutionרבן שמעון בן גמליאל is responding to the העמיד case
4. ChallengeA version of the משנה that seems to refute רב יהודה
5. Resolutionרב יהודה reads 'offspring' as 'they and their offspring'
6. ChallengeA second version of the משנה that seems to refute רב הונא
7. Resolutionרב הונא reads 'they' as the mother animals
8. StatementA ewe born to a goat: רבי מאיר and חכמים disagree
9. Questionרב הושעיא asks what רבי מאיר obligates
10. ChallengeIt cannot mean the firstborn מצוה
11. ChallengeIt also cannot easily mean the first shearing
12. ResolutionThe dispute is about the father in the law of 'it and its offspring'
13. ChallengeThen why not argue about the father in general?
14. ResolutionBack to firstborn: a ewe born to a ewe that came from a goat
15. ResolutionAnother case: a ewe born to a goat that came from a ewe
16. Resolutionרב אשי: an animal with only some of its mother's features
17. StatementEven רבי מאיר requires the ראש חודש goat to come from a goat
18. ChallengeIsn't this already learned from another פסוק?
19. ResolutionBoth פסוקים are needed
20. StatementNo מלקות for כלאים with wool from a changed animal
21. Statementרב פפא: Such wool cannot be used for תכלת
22. Statementרב נחמן בר יצחק: Such wool does not become impure with נגעים
23. Statementרב אשי: Wine from a vine trained over a fig tree is unfit for libations
24. Challengeרבינא: Then flax over a bush would also be changed
25. Resolutionרב אשי: The wine's smell changes, the flax's does not
26. Statementרבי יוסי הגלילי: twin males born together both go to the כהן
27. Statementחכמים: exact timing is impossible, so the כהן gets one
28. Statementרבי טרפון: the כהן picks the better lamb
29. Statementרבי עקיבא: they assess the lambs; the owner's lamb grazes until blemished