[Avodah] any makor

[Micha Berger]

Related is the subject of whether when Chazal specify a particular qiyum
of a deOraisa, did they therefore also "shut off" the ability to fulfill
it on the deOraisa level in other ways.

I would have thought pashut that they didn't. That someone who bentches
with sheim but not malkhus (e.g.) still fulfilled the deOraisa. That's
the basis of the Gra's wariness about saying Tzur miShelo -- it's
a qiyum deOraisa of bentching, leaving you wondering about actually
bentching afterward.

However, RCBrown blogged about this topic today. See first his post of
2006 at
http://divreichaim.blogspot.com/2006/11/where-failure-to-fulfill-din.html
    The Pri Megadim (Pesicha haKolleles 3:8) questions whether in a case
    where the Chachamim added extra criteria to the performance of a
    mitzvah and one failed to meet those criteria, is the kiyum d'oraysa
    of the mitzva also negated? One of the proofs to this issue comes
    from the case of a small sukkah which can fit a person's head and
    body but not a table -- although this sukkah is kosher m'doraysa,
    Tosfos (sukkah 3, brachos 11) writes that since it is pasul
    m'derabbanan one would not get any kiyum d'oraysa by using this
    sukkah.....
    When Rabban Gamliel's children came home past chatzos from a party,
    they asked their father whether they should recite kerias shema or
    not. Explains the PM"G, even though one cannot gain a kiyum mitzvah
    d'oraysa done deliberately not in accordance with the parameters set
    up by the Chachamim, here R' Gamliel's children missed the cutoff
    of chatzos only b'ones, unintentionally. R' Gamliel's children
    argued that violating a d'rabbanan b'ones should not negate a kiyum
    d'oraysa.....

Then, today's posting
http://divreichaim.blogspot.com/2010/02/takanah-derabbaban-to-listen-to-parshas.html
or http://bit.ly/bA8zLH
    [O]ff the cuff I was wondering whether this rule should apply to
    parshas zachor as well. M'doraysa there is no requirement to read
    parshas zachor this particular shabbos. According to many, if not
    most Rishonim, there is no need to ever do a formal krias hatorah to
    fulfill zachor -- one can simply "remember" Amalek through some
    verbal declaration .... Does that mean, based on the Pri Megadim,
    that one cannot fulfill the mitzvah d'oraysa in some other way,
    e.g. by hearing the parsha when Ki Teitzei is read in the summer?

Tir'u baTov!
-Micha

-- 
Micha Berger             You will never "find" time for anything.
micha at aishdas.org        If you want time, you must make it.
http://www.aishdas.org                     - Charles Buxton
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