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Eruvin 3b

עירובין ג׳ ע״ב

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Topic

How the twenty-אמה limit is measured, and which size אמה is used for סוכה, מבוי, and כלאים

Overview

רבא holds that the twenty-אמה limit for a סוכה and a מבוי is measured by the open space (חלל) underneath the סכך or the beam. רב פפא supports this from a ברייתא that uses the entrance of the היכל as its model. רב שימי בר רב אשי objects from a source that says the beam is placed 'from twenty and below.' The answer is that 'below' refers to the lower limit of ten טפחים, which is also measured by the open space. Next, אביי quotes רב נחמן: the אמה of סוכה and מבוי has five טפחים, while the אמה of כלאים has six, so each choice is the strict one. The גמרא tests this with minimum measurements where that אמה would actually be lenient: the length of a מבוי, רבי's four-by-four סוכה, and densely planted vines under רבי שמעון. Each time it answers either that רב נחמן follows the other opinion, or that he meant only 'most of the אמות.' רבא then reports רב נחמן differently: every אמה has six טפחים, but some are measured with spread fingers and some with fingers pressed together. A ברייתא is brought to challenge רבא's version, and it continues on the next עמוד.

Opening lines

חֲלַל סוּכָּה תְּנַן,

We learned about the space of the sukka,

חֲלַל מָבוֹי תְּנַן.

we learned about the space of the alleyway.

אֲמַר לֵיהּ רַב פָּפָּא לְרָבָא,

Rav Pappa said to Rava,

תַּנְיָא דִּמְסַיַּיע לָךְ:

A baraita was taught that supports you:

The steps (28)

  1. Statementרבא: the measurement is the inner space
  2. Proofרב פפא brings support from the Sanctuary entrance
  3. Challengeרב שימי objects: the beam goes from twenty and below
  4. Resolutionרב פפא changes the wording to 'and above'
  5. ChallengeBut the text clearly says 'below'
  6. ResolutionBelow works like above: the lower limit also measures the open space
  7. StatementWhich size cubit is used for סוכה, מבוי, and כלאים
  8. QuestionWhich מבוי laws use the small cubit
  9. ResponseThe small cubit applies to the height and the breach
  10. ChallengeThe minimum length of a מבוי would make the small cubit lenient
  11. Resolutionרב נחמן holds a מבוי only needs four טפחים in length
  12. ResolutionAlternatively, רב נחמן spoke only about most of the measurements
  13. QuestionWhich סוכה laws use the five-טפחים אמה?
  14. ResponseFor the סוכה's height and for a curved wall
  15. ChallengeThe minimum size of a סוכה would become more lenient
  16. Proofרבי's ברייתא: a סוכה must be at least four אמות by four אמות
  17. Resolutionרב נחמן follows the רבנן, who require no four-אמה minimum
  18. ResolutionEven according to רבי, רב נחמן meant most of the סוכה's אמות
  19. QuestionWhere is the six-טפח אמה of כלאים used?
  20. ResponseFor the vineyard clearing and the vineyard border
  21. ProofThe משנה giving the sizes of the clearing and the border
  22. ProofThe משנה defines a vineyard clearing
  23. ProofThe משנה defines a vineyard border
  24. ChallengeChallenge from vines planted less than four cubits apart
  25. ResolutionAnswer: רב נחמן follows the Sages
  26. ResolutionSecond answer: רב נחמן meant most cubits
  27. Statementרבא's version: every אמה has six handbreadths, measured loose or tight
  28. ChallengeA ברייתא is brought to challenge רבא's version