If the eruv was locked in a cabinet/tower (migdal) and the key was lost before bein hashmashot, requiring Torah-level labor to retrieve it, is the eruv valid?
Synopsis
If the eruv is locked in a migdal and the key is lost before nightfall such that retrieving the eruv requires Torah-level labor (e.g., demolishing the structure), the eruv is invalid. Discussion focuses on what counts as Torah-level labor and the case where the key is later found.
More in Shabbat Travelers and Eruv Boundary
If the validity of an eruv is in doubt (e.g., it is uncertain whether it existed at bein hashmashot), is it valid?
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Must an eruv be physically accessible (possible to take) at bein hashmashot, and what if it is buried under rubble requiring a shovel to retrieve?
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Until when must the eruv remain intact — only at bein hashmashot, or throughout Shabbat — and when may it be eaten?
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Discussion
Discussion coming soon.
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