yes hadith does have a very important status in islam infact its the second important source of islam after the quran.
the revelation is of 2 types apparent (jaly) and less apparent (khafy) the first type are the direct words and meanings from Allah and the second is only the meaning from Allah and the words r from the prophet peace be upon him.
So the first type is the quran and the second is hadith.
Another diff. between the 2 sources is that the transmission of both.....i.e the transmission is of 2 types (from the time of the prophet when it was revealed to today) :
1.
mutawatir
2.
not mutawatir
(mutawatir= transmitted thru many many ppl from generation to generation which makes it impossible to be a lie..)
Now the whole of the quran is of the 1st type and the hadith is of the first and second.
So that means the qurans transmittion has no faults and so we need not to research into it coz its so popular.
however the hadith's transmission is not the same and has different levels of transmission.....which inturn requires us to do a critical analysis of the transmitters!!!
u probably asking how hadith is transmitted??
well its easy .....for example imagine a teacher told A something then A told B and B told C ( sorry for choosing those letters u can use anythin u like!)
now there r 3 transmitters or narrators of the words of the teacher....so its like this:
teacher ->A->B->C
now u might say well this is like 'chinese whisper' ? well it does look that way....but no its not....to stop the words of the prophet (teacher) from being lost or confused or mixed up etc...the scholars of hadith would memorise the names of the narrators of the hadith when reciting the hadith ...so that why when u read books of hadith like bukhari ull see before the hadith is mentiond the names of chains of narrators...
then the scholars of hadith created a method by which they would categorize the narrators this was based on 2 things:
1.
piety (adalah)
2.
memory (hifth)
according to these two main factors the narrators were put in categories.....
but ure probably gonna say well how do they know the piety and memory of someone i mean did they record their 'life story'......well the answer is yes they basically did each narrators life is recorded from birth date to death date everything that would be required to find out the reliabilty of the narrator....this is known as the Art of Men (fan arijal / alm arijal)....there were also women amongst the narrators dont get confused by the name....
and the names of an amazing 500 000 narrators have been recorded.
Then this was continued upto the compiler of hadith like bukhari muslim tirmithi etc etc... and these compilations or books are of many types i.e. some of these books contain hadith in a jurisprudrent format some in order of names of narrators some on certain topics and so on...
thats a basic idea of hadith and trust me this is a very very short description.... u can read up books on hadith and the history of hadith for more info...
questions:
1. What is the role of the Hadith in Islam?
ans. second source after the quran and also and explanation for many principles in the quran e.g. the quran mentions salah ( pray) and the hadith explains how it is performed...
2. Are they to be taken as 100% authoritative, literal, and binding?ans. depending on the status of the narrators and strengthen of the hadith it is accpeted...but not always thats why at the end of many hadith the strength of the hadith is mentioned like sahih, hasan, dae'f.....and many books have been complied on hadith which are fabricated and not infact words of the prophet....
3. Or are there some that are just Mohammed speaking, and not God?
ans. muslims must obey Allah and muhammad peace be upon him.
Allah says: "You shall obey God and His messenger, that you may obtain mercy". [The Family of Imran, 132]
4. where does the Quran indicate that they are authoritative?
ans. Allah says: “Whatever the Messenger gives you take it, and whatever he forbids you abstain from it.” [Sûrah al-Hashr: 7]
(sorry for mistakes i made especially in english)
Hope this is of help ...Allah knows best.