Shevuos 28b

שבועות כ״ח ע״ב

Shevuot 28b

Learn Shevuos 28b step by step: Aramaic beside English, every question, answer and proof colour-coded.

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Topic

Conditional oaths on two loaves, the proof that a condition fulfilled by mistake does not count, and אבימי's test of עיפא on when a repeated oath takes effect.

Overview

The גמרא finishes its cases of a שבועה with a condition, like 'I will not eat this loaf if I eat that loaf.' When both loaves are eaten on purpose, the order matters. If he ate the forbidden loaf first, the warning he got was only a התראת ספק, and that depends on the dispute between רבי יוחנן and ריש לקיש. In a two-way oath, where each loaf is the condition for the other, he is liable only if he knowingly fulfilled the condition that made the other loaf forbidden. רב מרי supports this from the משנה in נדרים about mistaken vows, together with a ברייתא saying mistaken oaths are released too. Then the גמרא tells how אבימי tested his brother עיפא with three questions about repeated oaths, and corrected all three answers. An oath about the past is a new lie each time. A second oath only takes effect if it forbids something new. At the end, אביי starts showing that עיפא's 'ten then nine' answer can sometimes be right, using a case of רבה about figs and grapes that continues on the next amud.

Opening lines

The steps (20)

1. StatementBoth loaves eaten on purpose: condition loaf first, then the forbidden loaf
2. StatementForbidden loaf eaten first: depends on the dispute about an uncertain warning
3. StatementEach loaf conditional on the other: aware of each loaf's own oath, unaware of its effect on the other
4. StatementEach loaf conditional on the other: unaware of each loaf's own oath, aware of its effect on the other
5. StatementEach loaf conditional on the other: both eaten by mistake
6. StatementTwo-way oath with both loaves eaten on purpose
7. Proofרב מרי brings a supporting משנה about four kinds of vows
8. ProofThe cases of mistaken vows, and a ברייתא that applies them to oaths
9. ConclusionMistaken oaths must mean our case, so the proof stands
10. Questionאבימי tests his brother with two oaths about the past
11. Responseעיפא answers that he is liable only once
12. Rejectionאבימי: each past oath is its own lie
13. QuestionSecond question: nine, then ten
14. Responseעיפא: liable for each oath
15. Rejectionאבימי: ten is already forbidden by nine
16. QuestionThird question: ten, then nine
17. Responseעיפא: liable only once
18. Rejectionאבימי: the first oath still allowed nine
19. Statementאביי: sometimes עיפא's answer is right
20. Proofרבה's case: figs and grapes, then figs