fact is that after the dead of Holy Prophet Mohammad (PBUH) muslims divided into 2 main groups .. one the followers of Holy Prophet and His Family members (Fatima -Daughter, Ali - Son in Law and husband of Fatima, Hassan & Hussain - Grand sons & sons of Ali & Fatima (AS)) they are known Shias

And they consider them as Infallibles. Also most of the Shais (SYED Families roots comes from the Family of Holy Prophet) and Some root can be found in Sunnis too.

The difference start from the following sayings of Holy Prophet and Shias follows the follows this hadith very strongly  :

“I am about to answer the call (of death). Verily, I leave behind two
precious things (thaqalayn) amongst you: the Book of Allah and my Ahl
al-Bayt. Verily, the two will never separate until they come back to me
by the side of the Pond.”

Holy Prophet means to say that if you (Muslims) leave one of them you will be divided into group and will be beaten by enimies !!  which we are experiening today !

Other group who followed Sahabas (companion of Holy Prophet pbuh) Umar, Abu Baker Usman and Ali (Sunni consider Ali as their 4th Caliph and do not consider Ali as Infalliable) and other Sahabas... and majority of Sunnis follows the sayings of 1st three Sahabas mainly.

 

This is the main cause of indifferences within Shia and Sunni Muslims ... Although there are some Sunnis who follows the saying of Ahlylil Bait (Family of Holy Prophet ) and consider them infalliables .... but since Sunni themselves are divided into several sects and most of them differ from each others in terms of following the hadith (sayings of Holy Prophet).

 

To put on record, all the Family members of Holy Prophet were Martyr (Murdered by Muslims) for the control of Power during those times .... 

Those Muslims who bore the seeds of hatered, today it has become a huge tree !! 

 

Today Shai mourn those Martyr and Most of the Sunnis don't !!

 

These are the major indifferences among Muslims. Both Sects have strong believe in oness of Allah, His Holy Book "Quran" and last Prophet "Mohammad (PBUH)" Also five pillars of Islam, Prayers, Fasting, Eid etc.. everything is same .. only major dispute is follwing the sayings of Ahylil Bait OR Sahabas !!

Also there are some Sunnis and Shias who are striving for Unity and calls each others as Brothers in Islam.. but few sunnis (Wahabis) do not consider shia as Muslims and reject their believes according to Islam, here where the clash starts between two rivals. 

 

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