1a) Because the Koran states so:
a) No hadiths can be authoritative
4.87: Whose hadith (Ĥadīthāan) can be truer than Allah's?
6.57: The decision is for Allah only.
6.70: It hath beside Allah no protecting ally nor intercessor.
6.114: Shall I then seek a judge other than Allah?
7.185: In what HADITH (Ĥadīthin) after this will they believe?
9.31: They have taken as lords beside Allah their rabbis and their monks (Hanbal/Bukhari; imams and sheiks) and the
Messiah son of Mary (or Muhammad made into such an Islamic Messiah), when they were bidden to worship only One God.
12.111: It is no invented hadith (Ĥadīthāan) but a confirmation of the existing (Scripture)
and a detailed explanation of everything, and a guidance and a mercy for folk who believe.
31.6: Among the people, there are those who uphold baseless Hadith (Al-Ĥadīthi), and thus divert others from the path of GOD.
45.6: In which Hadith (Ĥadīthin) other than GOD and His revelations do they believe?
77.50: Which Hadith (Ĥadīthin), other than this, do they uphold?
There can be NO hadith confirming the Koran, since the Koran infirms them all at first!
b. No hadith whatsoever can be part of an Islamic Sharia:
3.78: And lo! there is a party of them who distort the Scripture with their tongues, that ye may think that
what they say is from the Scripture, when it is not from the Scripture. And they say: It is from Allah, when
it is not from Allah; and they speak a lie concerning Allah knowingly.
16.116-117: And speak not, concerning that which your own tongues qualify (as clean or unclean), the falsehood:
"This is lawful, and this is forbidden," so that ye invent a lie against Allah. Lo! those who invent a lie against
Allah will not succeed. A brief enjoyment (will be theirs); and theirs a painful doom.
c. The only Sunna is that of Allah (17.77; 33.62 35.43; 48.23).
48.23: It is the law of Allah (sunnata allahi) which hath taken course aforetime.
Thou wilt not find for the law of Allah aught of power to change.
http://tawhiyd.webs.com/sunnainquraan.htm3.19: The only religion approved by Allah is Islaam. Those who received the scripture dispute this fact, knowingly.
This is due to jealousy on their part. For those who reject Allah's revelations, Allah is most strict in reckoning.
3.85: Anyone who accepts other than Islaam as his religion, it will not be accepted from him...
Now go back and examine Qur'aan 17:77 and you will see that the "SUNNA" is in past tense, so therefore the "SUNNA" that is spoken of in the Qur'aan has nothing to do with the books called hadiyth (written by BUKHARI, TIRMIDHI, MUSLIM etc. which Sunni Muslims say is the sunna of Muhammad) that were again written in the future (AFTER) the revelation of Islaam (Al Qur'aan) and not BEFORE.... "Sunna Allah" is found in Qur'aan 48:23 and you will clearly see that it has nothing to do with hadiyth books written by BUKHARI, TIRMIDHI, MUSLIM etc. Please examine the verse below because we are dealing with the facts in the Qur'aan and not OPINIONS/STATEMENTS/ASSUMPTIONS/EMOTIONS by men: Again the "Sunna Allah" in that verse is in past tense
Also a link to Sam Shamoun over this question...
http://www.answering-islam.org/Shamoun/ ... _quran.htm
NOTE: there will be many more posts, each one dealing with a different aspect of this topic.