I've just quickly typed out some general historical differences from the Shia point of view.
I'm not looking for a debate - on this thread atleast.
The Prophet (pbuh) was a masoom (sinless) person; the word that is commonly used in English is infallible. I dont like using this word because the dictionary meaning suggests that it is someone who can not make a mistake, but this is not the case. The Prophets could make sins but they chose not to. Regardless, it is the closest word you can get to imply perfection through free-will.
He was married to Bibi Khadija (sa), and Abu Talib (ra) was the one who recited their nikah.
We dont believe Abu Talib was a kafir. The first public invitation, first ever Dawah that the Prophet (pbuh) made about Islam, famously known as Dawat-e-Zulasheera, where he had propagated about the religion among his close relatives, was in the house of Abu Talib (ra). In that gathering he had asked thrice I believe as to who will be assisting me in my divine job and every time Ali (as) had stood up. He was very young at that time so the Prophet (P) kept telling him to sit down, until finally the Prophet (P) acknowledged Ali and even at that time stated that he will be my vicegerent.
Anyways, Fatima Binte Asad (sa), the mother of Imam Ali (as) and the wife of Abu Talib (ra) had been near the Kaaba when she was near to the time to give birth to Imam Ali (as). By miracle the corner of the Kaba split open and she had went inside to give him birth and stayed in there for 3 days. So we say
Imam Ali (as) was born inside the Kabaa. I believe some Sunnis agree with that but most believe it was 'beside' the Kaaba. Till today the crack is visible on the Holy Kaba, the name of the corner is Rukn-e-Yamani and you will see many people trying to touch and kiss the corner. He had his eyes closed the whole time and later on the first person he saw was the face of the Prophet (P).
When Imam Ali was 7 years old, Abu Talib (ra) had given him under the guardianship of the Prophet (P) and he had always been under him since that age. During Shaib-e-Abi Talib, Abu Talib was also present and so was Khadija. It doesnt make sense for us that Abu Talib (ra) was spending 3 years in such conditions for the sake of the Prophet (P) to propagate his religion and then also give his son under his guardianship and then at the end of the day still be a kafir. The first dawah ever was given from the house of Abu Talib, his house is the starting point of Islam. Its not fair to suggest to non-Muslims that our religion started from a house of Kafir. Second of all, Fatima Binte Asad had become Muslim and it is well known fact that she had remained married to Abu Talib which also proves that he was a Muslim alongside the fact he read the nikah of the Prophet, a nikah that all Muslims still read till today. Now I can get into all the details and sources and what not but I dont think thats the purpose of this thread and I am simply stating what the general Shia view is. When Abu Talib and Khadija (sa) both died the Prophet (P) had declared the year of sorrow, but it is also well recorded that even during the later part of the Prophets life, he always remembered and mentioned Khadija.
She was in fact his favourite wife to the extent that some used to get jealous of her - as mentioned in the Bukhari.
Now coming towards the moot point differences; Surah Kawther was revealed, because the enemies of the Prophet (P) used to make fun of the Prophet as he had no son and were saying that no one will carry his lineage or his message forward. Even they knew, as history speaks for itself that when ever there was a Prophet (P) there had always been either their son or someone else who had executed the will of the previous Prophet (P). Someone who was a vicegerent and successor of the previous Prophet, whether it be Adam (as) or Muhammad (pbuh), every Prophet has someone after them as a successor or they appointed someone by the will of Allah (swt). Now Shias believe that Prophet Muhammad (Pbuh) is no exception to this rule and in fact we very clearly believe that the
Prophet (P) did in fact clearly state and imply that Ali (as) will be successor after me. Even in the Qur'an the ayah says Your wali is that who gives Zakat while in Ruku (5:55). This is a well known ayah about Imam Ali (as) when he gave his ring to the beggar in ruku. The final crunch point of this declaration came at the point of Ghadeer. The event and ahadeeth is perhaps one of the most authentic ahadeeth in both Shia and Sunni collections and it is mutawatir, meaning that it has come through many chains of narration.
It doesnt make sense to us that a Prophet (P) who had given us the details for every minute thing on how to deal with our lives, from praying, fasting, marriage, divorce, inheritance would not tell the people as to what to do after he passes away and just leave the whole Muslim ummah empty like that? When the Prophet (P) passed away Islam was not only a religion but it was a political power of the region.
At Ghadeer, in the crowd of thousands the Prophet gave a long sermon and in the sermon he took Ali with him on top of a pulpit made of up of saddles and raised his hand with his hand and said
Mun Qunto Mawla Fa Haza Aliyun Mawla. Sunnis translate this event to the fact that the Prophet (P) was pointing out to the people that Ali is his friend. But if you read the part of that narration before it says the Prophet says to the crowd of thousands that do
I not have more right over the believers than what they have over themselves? Everyone replies Yes and then after that he stated the part which we translate as for whomever I am the leader/master of, Ali is his leader/master. It doesnt make sense for
us that the Prophet (P) just took Ali in front of so many people just to tell them that he is my friend. I think over the span of 23 odd years of Prophet Hood people already knew that by now. Khair, this is where the major differences start to erupt. They say so how can so many people who were present there and heard this sermon then not go to Ali for his leadership. It is very easy to explain, first of all lets make it clear that after the Prophets death there clearly were some companions who were on the side of Ali and this was obviously for a reason. However for the rest, I have to say that when Musa (as) went to the mountain he had told his tens of thousands of companions that while I am absent Haroon will be your leader, but in a while or so, tens of thousands of companions of Musa had rejected Haroons authority and started to fall for the person named Samiri and started worshipping the cow. Even after the Prophet passed away the event of Ridda wars is in front of us, how can so many people turn apostates just within a year of the demise of the Prophet?
Anyways, this authority issue is the only major difference
and everything else pretty much revolves around it. Like everything. Because later on when history and hadeeth books are compiled both sides have their bias in their books from whom they take narrations and whom they deem weak or strong. Sunnis whether they like to admit it or not, unfortunately do not narrate much from the Ahlul Bayt (Ali, Fatima, Hassan and Hussain, or even Imam Jafar Sadiq). We don't believe this is a coincidence. However I wont hesitate to say this as well that Shia books on the contrary also do the complete opposite and we take narrations from the Ahlul Bayt which includes all the way till the 12th Imam (as) so both books are biased in their own ways its another thing that we dont necessarily see a problem in doing that.
Some other differences regarding what had happened after the Prophet (P). The general consensus amongst the Shias is that Bibi Fatima (sa) had died at the age of 18 due to rib injuries that she had received when Umar had pushed the door of her house and she was crushed between the knob and the wall at the same time having a miscarriage of her unborn baby Mohsin. Sunnis dont believe in this part they only accept till the part that Umar had just threatened to burn the door if Ali did not come out (to give allegiance to Abu Bakar). This is a whole event that is recorded in both Shia and Sunni books. Shias further believe that Imam Ali (as) was asked to be patient by the Prophet during this time and to not pull out his sword otherwise the religion of Islam would be at stake and he did this to the best of his ability. Regardless according to Sunnis, Imam Ali (as) did not give his allegiance for 6 months and Shias believe that this was a political move to finish the discrepancies (just like when Imam Hassan made treaty with Muawiyah) by no means does it mean that he agreed to his leadership it is also well known that Imam Ali (as) did not even fight battles under the caliphate of the first three caliphs. He was not taking part in the Ridda Wars during Abu Bakars time either. Even during the election of Uthman, Ali clearly rejected following the Sunnah of the first 2 caliphs, a question that was asked to him for a reason knowing very well that Uthman will agree to it (its another thing that he didnt really follow their sunnah either) which is why Ali was not chosen as the third caliph.
Another issue is the issue of Fadaq. The property of Bibi Fatima (sa) that she came to claim from Abu Bakar soon after the demise of the Prophet (P). Abu Bakar narrated a hadeeth where he said that the Prophet told him that they dont leave behind inheritance. This was a hadeeth that no one had heard and Bibi Fatima (sa) had openly debated him on this issue and proved him wrong from the Quran. She then gave a sermon, it is known as Khutba Fadakiya, and you can read it here:
http://youtube.com/watch?v=jRPznQ5nY28 It is funny to notice that apparently the daughter of the Prophet (P) did not even know about the inheritance ruling regarding herself from her own father who was the Prophet. We Shias can not imply falsehood on part of the daughter of the Prophet who is the mistress of the all the women of paradise and is also mentioned as the purified one in verse 33:33. We can not imply that she was ignorant of this simple ruling and that she was using Quran to prove something that was false. Anyways, Abu Bakar never gave it back and it is recorded that
Fatima left angry with Abu Bakar and when she died she instructed Ali that dont let these people come to her burial. Thats why till today her exact burial place is a secret but commonly accepted as the one at Jannatul Baqi. The garden of Fadak was played around with back and forth even during the Bani Ummayah time, until when
Umar ibn Abdul Aziz came into power and he returned Fadak to Imam Mohammad Baqir (as) who is the grandson of Bibi Fatima (sa).
Leaving alone the caliphate rule of Umar and Uthman and coming to the rule of Ali: the first thing we see is the
Battle of Jamal with the wife of the Prophet Ayesha. Sunnis at least agree here that Ayehsa had made a mistake in this case. But unfortunately one day on a camel and
then again on a mule to prevent the burial of Imam Hassan (as) beside the Prophet (Pbuh) and where Marwan had come with his soldiers to fire arrows at the dead body of Imam Hassan (as). His burial was then diverted to where he is buried today Janatul Baqi. Just quick reasons why we dont see her in good light and we very explicitly believe that she was going against who the Prophet had said is on haq and haq is with him (Ali). Before even going against Ali in war, she clearly went against the Quran by coming out all the way to Basra with an army of thousands. Some Sunnis say we dont like Ayesha because she was the daughter of Abu Bakar, but this is false because on the contrary we respect and keep Muhammad ibn Abu Bakar in high regards who at the battle of Jamal was in fact fighting against his own sister. Qur'an also condemend her in Surah Tehreem after the
maghafir incident.
The other war was battle of Sifeen between Ali and Muawiyah who we hate with passion. I can keep going on and on about Muawiyah and how corrupt he was and it is the one person that I dont understand why Sunnis respect surely being a mere Sahaba can not justify the crimes of this man. It was during his time the cursing of Imam Ali was initiated from the pulpits and anyone who loved or praised Ali was usually killed like many of the Sahabas were. The cursing of Ali from the pulpits was stopped years later by Umar ibn Abdul Aziz. Then once again he broke the treaty with Imam Hassan (as) and put his son Yazeed into power. Notice how everyone was smart enough to put a successor after them but the Prophet didnt makes us think too. Khair, then I dont think I need to tell what Yazeed did and the event of Karbala is apparent. Some Wahabis think that Yazeed had no role or involvement in Karbala but that is the biggest joke ever. Many dont even know what happened after Karbala, the ladies were taken to the court of Yazeed in Syria and they were kept prisoners in his jails for 1 year. The event was the climax so to say. After that, most average people arent aware of the Ummayad caliphs and Abbasid caliphs and what they were up to and dont think they matter that much in this thread for the most part. Basically the love of Ahlul Bayt is wajib as mentioned in the Qur'an and obviously in ahadeeth as well and anyone who hurts the chosen family of the Prophet is going against the teachings of Islam and therefore we can not view them in good light and it is an unfortunate fact that the family of the Prophet had had to see such unfortunate times and days after the death of the Prophet by the people who were supposed to be Muslims and the Sahaba of the Prophet.
That was a very brief, quick and general over view on our take of historical events. In terms of fiqh, we differ on issues like divorce we dont do the Talaq Talaq Talaq and say Umar started it during his rule. We dont say Salato Khairum Minan Naum and say Umar started that as well. Same goes for Tarawih, it was never done in Jamaat by Prophet Umar started it as well during his time. We also have 5 Takbirs in Namaz-e-Janaza, we also recite Talqin when burying the dead body in a grave and we recite Bismillah out loudly in every Namaz. Also do Wudhu a bit differently, and all Shias pray with their hands on their sides and do Sajda on anything that is earth and natural and not something that is man made material like something you can wear (cloth, carpets etc).
Now everything I mentioned above, one can debate on and on over each point but I am really
not looking for a debate, kinda not bothered and Ill be leaving the country in a while as well. I shared how my view point differs and anyone else can please feel free to share their view instead of trying to start debates with what Ive said above. If you want to have a debate on anything feel free to open a new thread and Ill be more than happy to take part in it.
Edit - Oh ya I forgot to mention. After the demise of the Prophet (P), many of these companions of the Prophet were not even at his burial and were at
Saqifa choosing who would be the caliph where on the other hand many of the other Sahaba didn't even know what was going on at Saqifa.
Anywyas, all I can say again is you need to
read books and take some initiative yourself. Otherwise anything anyone will say will go over your head because you won't understand it - like it has been for the past year or two.