“Question: Is one permitted to perform a melocho d’orayso with a shinui for a choleh?
Discussion: The Tur (Orach Chayim Siman 328) rules that it is permitted to ask a non-Jew to perform any melocho for a choleh she’ein bo sakono. In a situation of sakonas eiver it is also permitted for a Jew to perform a melocho d’rabonon.
The Tur quotes his father the Rosh who deliberated as to whether it is permitted for a Jew to perform a melocho d’rabonon himself for a choleh she’ein bo sakono. The Beis Yosef (ibid) explains the doubt of the Rosh: Can we extrapolate from amirah le’akum, which is an issur d’rabonon and permitted in a situation of choli to other issurei d’rabonon, which should likewise be permitted in a situation of choli, or should we differentiate between amirah le’akum which is a “passive” issur d’rabonon and other issurei d’rabonon which are (generally) “active” [i.e. they involve an action, which is more severe than mere speech].
The Tur and Beis Yosef quote various opinions in the Rishonim who rule in this situation: The Rashbo is lenient, and the Ran is stringent. The Rambam also rules leniently (the Tur and Beis Yosef differ as to whether the Rambam is lenient in all situations, or whether he only permits those issurei d’rabonon that have no connection to a melocho d’orayso), while the Ramban permits a Jew to perform a melocho d’rabonon with a shinui for a choleh she’ein bo sakono.
The Shulchan Aruch (Orach Chayim Siman 328 se’if 17) discussing a Jew performing a melocho d’rabonon quotes all opinions who discuss this situation, and concludes that it appears that the third quoted opinion; i.e. the opinion of the Ramban (this is how the Magen Avraham s.k. 14, Taz s.k. 12 and Mishna Berura s.k. 57 understand the Shulchan Aruch) is the correct one to follow; i.e. for a choleh she’ein bo sakono a Jew may perform an issur d’rabonon with a shinui. The conclusion of the Shulchan Aruch is upheld by the major authorities (i.e. Magen Avraham, Taz, Mishna Berura and it appears from the lack of comment that the Remo agrees to this also) and is the accepted ruling.
In summary: A Jew may perform on Shabbos an issur d’rabonon with a shinui for a choleh she’ein bo sakono.
It appears from this se’if that the only deliberation is about performing an issur d’rabonon for a choleh; we have not seen any dispensation for a Jew to perform a melocho d’orayso even with a shinui for a choleh she’ein bo sakono. It is also clear from the Mishna Berura in several places (Siman 328 s.k. 57; s.k. 107; see also Sha’ar Hatziyun Siman 496 s.k. 9) that there is no allowance to perform a melocho d’orayso with a shinui for a choleh she’ein bo sakono.
However, we do find mention in several of the Poskim (Graz Siman 328 se’if 19; Tehilla l’Dovid Siman 328 se’if 22; Iglei Tal Tochein #18; Ketzos Hashulchan Siman 134 se’if 4; Rav Shlomo Zalman Aurbach quoted in Shmiras Shabbos Kehilchoso Perek 33 footnote 18) a leniency to allow one to perform a melocho d’orayso with a shinui for a choleh she’ein bo sakono.
The rationale of these authorities is that a melocho d’orayso performed with a shinui is more lenient than a regular issur d’rabonon (we find this idea also mentioned in Rashi Pesochim 66b). They claim that if it is permitted to perform an issur d’rabonon for a choleh, all the more so it is permitted to perform a melocho d’orayso with a shinui.
Conclusion: Although the Mishna Berura clearly does not permit performing melochos d’orayso with a shinui for a choleh, in extenuating circumstances where there is no alternative one may rely on the lenient opinions and perform a melocho d’orayso with a shinui for a choleh she’ein bo sakono.
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