Kesubos 15a

כתובות ט״ו ע״א

Ketubot 15a

Learn Kesubos 15a step by step: Aramaic beside English, every question, answer and proof colour-coded.

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Topic

Following a majority for lineage: the double-majority rule, the principle that anything קבוע counts as half and half, and רב's ruling about רבי יוסי

Overview

The גמרא says the earlier incident happened at the wagons of ציפורי. It explains, using רבי אמי and רבי ינאי, that a woman is fit for כהונה only when both the city and a passing group are mostly of proper lineage. If one man came out of the city alone, the child is a שתוקי. A teaching that we follow the city's majority and not the group's is challenged as backwards. It is reread to mean that two majorities are needed. Neither one alone is enough, because a man whom she went to inside the city is קבוע, and קבוע counts as half and half. The meat-store ברייתא seems to show that one majority is enough. The answer is that חכמים set a higher standard for יוחסין. The גמרא then finds רבי זירא's source that קבוע counts as half and half even when this leads to leniency. It brings the case of nine שרצים and one frog, and the Torah source is the פסוק 'וארב לו' about a stone thrown into a group. Finally, two reports of רב disagree about whether the הלכה follows רבי יוסי. רבי ירמיה begins a challenge from a משנה that continues on the next amud.

Opening lines

The steps (29)

1. StatementThe incident happened at the wagons of ציפורי
2. Statementרבי ינאי: relations in the wagons leave her fit for כהונה
3. ChallengeCould it really have happened in the wagons?
4. ResolutionIt means at the time the wagons pass
5. StatementIf one man left ציפורי, the child is a שתוקי
6. Proofרב דימי's report: follow the city's majority, not the group's
7. ChallengeThe opposite makes sense: moving versus fixed
8. ResolutionTwo majorities are needed: the city and the passing group
9. ChallengeSometimes the city's majority should also work
10. ResolutionThe decree is for when she went into the city
11. ChallengeThe meat stores show one majority is enough
12. RejectionThe open-gates answer is rejected
13. ResolutionA higher standard for lineage
14. StatementAnything fixed in place counts as half and half
15. QuestionWhere does this rule come from?
16. ProofFirst try: the nine stores
17. RejectionThe stores case only shows the strict side
18. ProofSecond try: nine frogs and one שרץ
19. RejectionThe frogs case is also only strict
20. ResponseThe real source: nine שרצים and one frog
21. QuestionWhat is the Torah source?
22. ResponseThe verse about lying in wait
23. QuestionHow do the רבנן use the verse?
24. ResponseExcluding a stone thrown into a group
25. ChallengeWhy would we need a verse for this case?
26. ResolutionNine Jews and one fixed gentile
27. StatementFirst report: the הלכה follows רבי יוסי
28. StatementSecond report: it was a one-time ruling
29. ChallengeDo lineage cases really need two majorities?