Reasons For Absence Of Unity Among Muslims
The foremost reason for the lack of unity among muslims is that they, for all practical purposes, abandoned Quran very early on after the demise of Holy Prophet and created sects based on: 1. Historical events and their interpretation, 2. Personality cults around the family members and friends of the Prophet, 3. Weak and fabricated traditions which suited their specific cult. As a result, they put the supremacy of God and His message delivered by Holy Prophet behind their back, and started quarrelling over the supremacy of their fellow human beings as infallible religious authorities. Quran tells us that Prophet will complain before God on the DoJ that his people abandoned Quran (25:30). Since Quran has been preserved with impeccable integrity and it contains clear and unambiguous commandments, Muslims had the opportunity to stay united by acknowledging its supremacy and holding strongly to it as it is habl ullah (rope of God). But they lost this opportunity just like Jews and Christians before them who after having received the word of God, created differences among them: 45:17 We gave them proof in the matter, but then they disputed after the knowledge had come to them, out of jealousy amongst themselves. Your Lord will judge them on the day of resurrection regarding everything that they have disputed. 3:19 The system with God is peacemaking and peaceful surrendering (islam). Those who received the book did not dispute except after the knowledge came to them out of jealousy between them. Also see 2:213. The only way Muslims can unite is by: 1. Finding common grounds based on the message of God, and 2. By independently studying Quran without the bias and prejudice of their sectarian teachings and their respective religious books of history and traditions, and 3. By drawing clear lines between Islamic history and historical events and actual islam.