Why is it that a seemingly minor issue surrounding succession of the caliphate has become a major division within Islam (Sunni/Shia)?
First of all, we are to worship how our Creator taught us. In doing this, you will be able to see the direction that is the most authentic to the belief in Islam.
It is taught that we are to follow explicitly the way our Creator taught us through the Quran and then the Sunnah. The Quran which is the words of our Almighty God and then the teachings of Mohammad, his last messenger and servant...they compliment each other. Example: Allah says to pray 5 times a day, and in learning how to pray there are the teachings from the messenger of Allah on just how to do it properly.
In saying this, the record of ahadith are kept genuine. There are ways to follow up on which is authentic and which are not.
In Islam, we are to not worship any other than Allah and to follow what he says and we are given strict instructions to follow Mohammad and his teachings.
There is proof to which is correct in Islam.
In Shia'ism, there are things that go against the Quran and Sunnah.
Major disbeliefs. So we can say that the differences there are those who are not following the Quran and Sunnah. They are many sects that deviate from the true path of Islam. The ones who follow the correct path know that by no way they would believe against what the Quran and Sunnah have taught. In this, they have every right to refrain from such events and beliefs.
“O you who believe! Obey Allah and obey the Messenger (Muhammad (blessings and peace of Allah be upon him)), and those of you (Muslims) who are in authority. (And) if you differ in anything amongst yourselves, refer it to Allah and His Messenger (blessings and peace of Allah be upon him), if you believe in Allah and in the Last Day. That is better and more suitable for final determination”
an-Nisa’ 4:59.
It is confirmed that the Messenger of Allah (peace be upon him) said:
“The Jews split into seventy-one sects; one will be in Paradise (i.e., those who followed Moses) and seventy will be in the Fire. The Christians split into seventy-two sects; seventy-one will be in the Fire and one will be in Paradise (i.e., those who followed Jesus). And by the One in Whose Hand is the soul of Muhammad, this Ummah (nation) of mine will split into seventy-three sects; one will be in Paradise and seventy-two will be in the Fire.
It was asked, “Who are they, O Messenger of Allah?”
He (peace be upon him) said, “Al-Jama‘ah (i.e., the group which adheres steadfastly to the way of the Prophet, peace be upon him, and his Companions).”
