The fact is that Sahih Bukhari (the most well known compilation of ahadith)
was compiled and codified 600 years after the Prophet died. How can it be as
authentic as the Quran which was codified within the same generation?
The argument is absurd on the face of it.
Take a look at this thread.
http://www.interfaith.org/forum/unreliable-ahadith-regarding-the-return-10616.html
In it a few key hadiths from the most respected collections of ahadith
(Bukhari and Muslim) have been proven to be unreliable. So even if these
compilations contain inauthentic ahadith, what does it say about the rest?
Also, the comment I made to you on which you have based this thread needs to
be put in proper context. You were quoting a very harsh fatwa by some
lunatic mullah who was saying that a person who does not fast is automatically
a kaffir (unbeliever). Even if this fatwa is based in a hadith, it is totally refuted by the Quran.
No where in the Quran does anyone have the authority to question the faith of
another individual as God clearly says that He knows what is in a person's heart. (28:69)
So even if this fatwa is based in some obscure hadith, then that hadith is automatically
negated by the Quran. I also have heard hadiths which would contradict this idea.
This was the context in which I made that above remark.
There is another verse in which Allah says that He knows the real Muslims from the
Hypocrites (29:11) but if you will notice the history of Muslims in Medinah, those who were
suspected to be hypocrites, were still treated as Muslims even after they refused to stand
with the Muslims when they were attacked by their enemies. Their leader's funeral was even
attended by the Prophet himself and he said a prayer for him, the same as we always did for
other Muslims. So even the Prophet himself was not judging other Muslims on their faith even
those who were obviously hypocrites. So for these mullahs to issue these fatwas declaring
who is a muslim, and who is not, is clearly wrong. And any hadith which they quote to support
their fatwas is also automatically false.