Rejection of Ahadith

Why do some people reject hadith? The answer is quite simple - ignorance. Hadith-rejectors are not scholars who have studied the sciences of Hadith and the meticulous system of classification behind them. They are laymen who have no education in Islamic sciences, come across some hadith that they don't understand or that seems problematic to them, and conseuqently they conclude "It doesn't make sense to me, therefore it can't be true!"
And please give me the Quran verse that states that in order to be a Muslim you must believe in hadiths
The problem is you do not understand what the hadith and the hadith compilations are. The Qur'an commands us to follow the way of the Prophet Muhammad pbuh and accept his teachings. In fact it negates the faith of anyone who fails to do so:
4:65 But no, by your Lord (O Muhammad), they have no Faith, until they make thee judge in all disputes between them, and find in their souls no resistance against thy decisions, but accept them with the fullest conviction.
Please give me the Quran verse that talks about Buhkari and the others that have recorded hadiths. With all due respect, where have these people been mentioned in the QUran? Who has given them authority? Does God speak of them?
This is another one of your miscocneptions. We don't accept the hadith in Sahih Bukhari
because they were compiled by Imaam Bukhari. We accept them because they have gone through the most rigorous process of authentication by the scholars, and the efforts of the Muslim scholars for over a millenia have confirmed their authenticity. You misunderstand the function of the compilers of hadith - they were collecting the hadith that had already been recorded and transmitted and after authenticating them included them in their collection. And the efforts of the hadith scholars were built on the efforts of those who preceded them and confirmed by the efforts of those who came after them. Why hasn't Sahih Ibn Hibban achieved the status of Sahih Bukhari? Was it because Imam Ibn Hibban was any less of a scholar? No, it is because the hadith in Sahih Ibn Hibban went through the authentication process and the scholars found some hadith to be inauthentic, so overall the compilation does not hold the same status as Sahih Bukhari which has unanimously been upheld to be completely authentic by the Muslim scholars.
...the hadiths recoreded years after the Prophet's death.
Myth. The hadith were recorded during the Prophet's lifetime by the companions; see br. kadafi's post here:
ALL MYTHS ABOUT AHADEETH DEBUNKED HERE
Why would God leave it up to us to decide what is authentic and what is not authentic?
He didn't leave it up to you - you don't understand the rigorous process behind the authentication of hadith because you have never studied that science. Yet for some reason you have the audacity to pass judgement on a subject you are ignorant of! Ahadith are not authenticated by some randomized process - the content as well as the chain of narration for each hadith is studied carefully to determine its authenticity, and this isn't done by just one scholar - this is the collective efforts of all the Muslim hadith scholars throughout Islamic history.
Another point - it is always amusing to note hadith rejectors says, "But some of these hadith contradict the Qur'an". They forget that one of the requirements for a hadith's authenticity is that it be in accordance with the Qur'an, so the scholars of hadith
already checked that before passing their judgement on it. What a hadith rejector really means when they make such a comment is that the hadith contradicts
their ill-informed and mistaken understanding of the Qur'an.
See the following thread where three hadith rejectors' arguments were utterly devastated:
http://www.islamicboard.com/basics-islam/15909-hadith-women.html
They made the claim that some authentic hadith contradicted the Qur'an, but they failed to provide even a single example to support their claim.
Prove to me how those hadiths are mandated in the Quran... prove to me how God mandated those things.
You're asking the wrong question. If we agree that God mandated for us to follow the Prophet pbuh, then the question should be whether these hadith are authentic in what they ascribe to the Prophet. By mandating obedience to the Prophet, God has mandated for us to follow all of the sayings and teachings of the Prophet which have been authentically transmitted to us.
Surah 18:54
We have explained in detail in this Quran for the benefit of mankind, every kind of similitude: but man is, in most things, contentious.
If you think this verse is saying that there is no need for information beyond the Qur'an, then you haven't read the entire Qur'an:
Qur'an 16:44 And We have also sent down unto you the reminder, that you may tubayyina (EXPLAIN CLEARLY) to men what is sent down to them, and that they may give thought.
If al that we need was the verses of the Qur'an, then why would Allah swt ordain for the Prophet pbuh to explain what had been revealed? This clearly means that the explanations are themselves divinely ordained by Allah.
For more information, please refer to br. kadafi's post which concisely debunks the prevalent myths amongst hadith rejectors:
http://www.islamicboard.com/212874-post5.html
