Eruvin 89b

עירובין פ״ט ע״ב

Learn Eruvin 89b step by step: Aramaic beside English, every question, answer and proof colour-coded.

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Topic

Carrying on roofs: רב versus שמואל, רב יוסף's forgotten teaching, and how building or not building shows a claim to the roofs

Overview

Background: רב holds that on roofs you may carry only within four אמות, while שמואל allows carrying across a whole roof. The amud opens with the end of the משנה's phrase 'each roof is a domain in and of itself.' That seems to support שמואל, but בי רב reread it as a restriction: you may not split your four אמות between two roofs. A ברייתא of בי שמואל, 'they have only their own roof,' is explained the same way. רב יוסף, who forgot his learning after an illness, says he never heard שמואל's teaching. His student אביי reminds him that he taught it about a large roof next to a small one, in a version that depends on people living on the roofs. רב יוסף remembers, but corrects it: the rule depends on real walls fit for living. If only the large roof has such walls, the small-roof owners have given up their claim, so even the small roof is permitted to the large roof's people. The גמרא backs this up with רב נחמן's fixed ladder and אביי's upper room with a small wall (דקה). Both show that whoever prepares the roofs for use gets them. רבא then begins to explain when the small wall leads to a prohibition instead: when it faces the owner's own garden. That explanation continues on the next amud.

Opening lines

The steps (18)

1. ChallengeThe משנה's phrase seems to fit שמואל, not רב
2. Resolutionרב's students: the משנה is a stringency, not a leniency
3. Challengeרבי אלעזר's report from Babylonia
4. ChallengeSpelling out the meaning of 'only their own roof'
5. RejectionThe ברייתא is no stronger than the משנה
6. ResolutionThe ברייתא also means no splitting between two roofs
7. Statementרב יוסף says he never heard this teaching
8. Proofאביי says רב יוסף taught it himself, on the case of a large and small roof
9. Proofאביי repeats שמואל's teaching about residents on the roofs
10. Rejectionרב יוסף remembers but corrects the version: it depends on walls, not residents
11. Challengeאביי objects: you spoke about residents
12. Resolutionרב יוסף explains: 'residents' means walls fit for living
13. StatementWhen only the big roof has walls, even the small roof is permitted
14. ProofSupport from רב נחמן's fixed ladder ruling
15. Statementאביי: building an upper room with a small wall permits all roofs
16. StatementSometimes the small wall leads to a prohibition
17. QuestionWhat is the case?
18. ResponseThe small wall faces the garden of his house