[Avodah] Lo Ra'inu Eino Raya ==> Blanket Heter

[Chana Luntz]

As an addendum to this thread, I would note the gemora in Neddarim 15a -
which states "devarim hamutarim v'acherim nohagu behem issur i ata rashai
l'hitiran bifnehem"  - ie matters which are permitted, but others are
accustomed to treat them as prohibitted you are not permitted to permit them
before them "shenemar lo yachel" although the gemora clarifies that this is
in fact a rabbinic form of bal yachel.

Of course when and where this applies is subject to a good deal of
discussion - but it certainly makes clear that Shas itself does not believe
that something that is instrinsically mutar is permitted.  Rather the
opposite, if you permit it where people have been accustomed to forbid, you
may be over on a rabbinic issur.  Also note that Rav Ovadiah Yosef in
Yacheve Daat (Chelek aleph siman 38 - following on from others who also use
this time a year as an example) uses this gemora as the justification for
prohibiting certainly warm showers (if not cold showers for those who follow
the Rema) during shavua shechal bo tisha b'av - despite acknowledging it to
be mutar to so bathe according to Shas up until the seuda mafseket.

Regards

Chana