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Eruvin 79b

עירובין ע״ט ע״ב

Learn Eruvin 79b step by step: Aramaic beside English, every question, answer and proof colour-coded.

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Topic

The hay partition between courtyards, ביטול רשות, the משנה on making a שיתוף for a מבוי, and the rulings of the elders of פומבדיתא

Overview

The amud opens by finishing a ברייתא about hay between two courtyards. In רב הונא בריה דרב יהושע's case the hay is only a little over seven טפחים, yet it counts as ten because of לבוד, so "less than ten" means "less than the law of ten." The גמרא tries to prove from "both are forbidden" that דיורין הבאין בשבת אסורין, but it rejects the proof: the hay may have shrunk before שבת. The ברייתא's fix is to lock one's house or renounce one's rights (ביטול רשות). The גמרא shows that one cannot renounce rights and then have them renounced back. It also shows that the hay rule applies between two תחומי שבת without any extra גזירה, even for רבי עקיבא. A new משנה then explains how one person makes a שיתוף for a מבוי through someone independent of him who acquires it for everyone. רב יהודה adds that the barrel must be lifted a טפח. This leads to a list of rulings by the elders of פומבדיתא: a cheekful of wine for קידוש, a fire on שבת for anyone endangered by cold, and the definition of a presumed אשירה, which continues on the next amud.

Opening lines

וְתֶבֶן שִׁבְעָה וּמַשֶּׁהוּ,

and the hay is seven and a little more,

דְּכׇל פָּחוֹת מִשְּׁלֹשָׁה

because anything less than three

כְּלָבוּד דָּמֵי.

is considered as joined (לבוד).

בִּשְׁלָמָא לְאַבָּיֵי,

Granted, according to Abaye,

The steps (25)

  1. StatementHay slightly over seven handbreadths counts through לבוד
  2. ChallengeHow does "less than ten" fit רב הונא's case?
  3. Resolution"From ten" means "from the law of ten"
  4. ProofDo residents added on שבת forbid carrying?
  5. RejectionMaybe the hay shrank before שבת
  6. StatementHow one resident can permit the other
  7. ChallengeWhy are two actions needed?
  8. ResolutionIt means either one
  9. ResolutionOr both really are needed
  10. StatementHe is forbidden and his neighbor permitted
  11. ChallengeIsn't that obvious?
  12. ResolutionYou cannot renounce back and forth
  13. StatementThe haystack rule also applies between two תחומי שבת
  14. ChallengeWhy say something so obvious?
  15. ResolutionNeeded according to רבי עקיבא: no extra decree
  16. StatementHow to make a shared food-merger for an alleyway
  17. StatementWho cannot acquire for the residents
  18. StatementThe barrel must be lifted a handbreadth
  19. StatementTwo teachings of the elders of פומבדיתא
  20. StatementA third teaching: a fire for a woman after childbirth
  21. StatementA narrow reading of the fire ruling
  22. RejectionFire is allowed even in summer for anyone chilled after bloodletting
  23. Statementאמימר adds another ruling from the elders of פומבדיתא
  24. QuestionWhich tree is presumed to be an אשירה?
  25. Responseרב: a tree that idolatrous priests guard