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Eruvin 11a

עירובין י״א ע״א

Learn Eruvin 11a step by step: Aramaic beside English, every question, answer and proof colour-coded.

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Topic

The limits of a מבוי entrance (height and width), whether a צורת הפתח or an אמלתרא can fix them, and whether רבי יוחנן agrees with רב that a צורת הפתח cannot fix an opening wider than ten אמות.

Overview

This עמוד continues the rules for the entrance of a מבוי: the cross-beam may not be higher than twenty אמות, and the entrance may not be wider than ten אמות. A ברייתא shows that a צורת הפתח fixes a beam that is too high. The גמרא tries to prove from another ברייתא that an אמלתרא fixes an entrance that is too wide, but the proof is rejected. רב then corrects a ברייתא to teach that a צורת הפתח does not fix an entrance wider than ten אמות. רב יוסף tries to extend רב's rule to a חצר whose walls are mostly open, but the comparison is rejected, and so is a supporting ברייתא, which רב כהנא explains as speaking about broken entrances. The גמרא then tries to show that רבי יוחנן agrees with רב, using a story about poles and a vine around a field, where רבי יוחנן and ריש לקיש argue about שבת. That proof is pushed off: the argument may be about רב חסדא's rule on a side-attached צורת הפתח. The עמוד ends by announcing a contradiction within each of רבי יוחנן and ריש לקיש, and the source for it continues on the next עמוד.

Opening lines

אִיפְּכָא מַאי?

The opposite — what is [the law]?

תָּא שְׁמַע דְּתַנְיָא:

Come and hear, as it was taught:

מָבוֹי שֶׁהוּא גָּבוֹהַּ מֵעֶשְׂרִים אַמָּה יְמַעֵט,

An alleyway that is higher than twenty cubits must be lowered,

וְאִם יֵשׁ לוֹ צוּרַת הַפֶּתַח

but if it has a doorway-frame

The steps (26)

  1. QuestionWhat about the reverse case?
  2. ResponseA ברייתא says a doorway-frame fixes the height problem
  3. QuestionDoes a cornice fix an entrance that is too wide?
  4. ProofQuoting a ברייתא that mentions the cornice
  5. ProofSpelling out the proof: the cornice refers to the width case
  6. RejectionRejected: the cornice may refer only to the height case
  7. Statementרב corrects the wording of the ברייתא: the wide entrance must be narrowed
  8. Statementרב יוסף learns a rule about a courtyard from רב's ruling
  9. ProofThe reason: comparing the wide מבוי to the mostly-open courtyard
  10. RejectionThe comparison fails: the two problems are not equally severe
  11. ProofA ברייתא seems to support רב יוסף
  12. ChallengeThe wording of the ברייתא contradicts itself
  13. ResolutionCorrecting the ברייתא to 'he added many openings'
  14. Rejectionרב כהנא: the ברייתא is about broken entrances
  15. QuestionWhat are 'broken entrances'?
  16. ResponseMissing doorposts or missing lintel
  17. Statementרבי יוחנן also agrees with רב
  18. ProofThe man who put poles at the corners of his field
  19. Statementריש לקיש and רבי יוחנן argue about שבת
  20. QuestionWhat exact case is this?
  21. ChallengeIt cannot be a vine attached to the side of the poles
  22. ResolutionThe vine was on top of the poles
  23. ChallengeIt cannot be poles only ten אמות apart
  24. ProofSo the poles must have been more than ten apart
  25. RejectionNo, the gap was ten and the vine was attached from the side
  26. ChallengeEach אמורא seems to contradict himself