[Avodah] Just what ARE the rules of p'sak anyway?

[Yitzhak Grossman]

On Mon, 5 Nov 2007 18:50:52 -0500 (EST)
"Micha Berger" <micha at aishdas.org> wrote:

> For example, the problem nearly everyone has with hafkaas qedushin.
> There is no textual basis for extending "kol demeqadeish adaas
> derabbanan meqadeish" in an era where there is no institution one can
> point to as being the locus of "daas derabbanan". Today, one would
> have to ask, which rabbanan? (Looking at the rishonim, the machloqes
> seems to be whether geonim had such authority. Hakol modim they
> didn't.) There is no minhag avos support for such things, no historic

By "Hokol modim they didn't", I understand you to mean that all agree
that Rishonim do not have the authority to nullify Kiddushin.  This is
not correct; the most sensational account of a post-Talmudic afke'inhu,
and the only one I know to have occurred without a preexisting edict,
and justified solely by a perceived Rabbinic fear of a potential future
socio-religious catastrophe, is this one of the Darkei Moshe [0]:

--- Begin Quote ---

[Quoting the T'rumas Ha'deshen:] But in the [aftermath of the] decree of
Austreich they [women who had been captured by gentiles - see the
previous section of the DM] were permitted, on the authority of
Gedolim, to their husbands too, even to Kohanim ...

[The DM himself:] And it seems to me that perhaps the Gedolim who
permitted did not do so Mi'dina but for a Zorech Sha'ah, for they saw
that we must be concerned for future women, that if they were to know
that they would be unable to return to the husbands of their youth,
they might sin, and so they were lenient.

And do not say, can we be lenient with regard to an Issur De'oraisa?
It seems to me that they relied on that which it is stated "kol
d'me'kadesh a'da'ata d'rabbanan m'kadesh" and Beis Din has the
authority to nullify their Kiddushin and they are therefore as single
women and even if they have strayed they are permitted to their
husbands, so it appears to me.

--- End Quote ---

[I came across this once in an article by Rabbi Riskin, but could not
recall the DM's location; a friend tracked it down for me.]

[0] EH 7:13

Yitzhak
--
Bein Din Ledin - bdl.freehostia.com
An advanced discussion of Hoshen Mishpat