Expand my breast...
Expand my breast; ease my task; and give me a Minister from my family, Ali, my brother; add to my strength through him, and make him share my task". Abu Dharr concluded: "By God, as soon as the Prophet completed his prayer the trustworthy Gabriel came with the following verses: "Your guardians are God, His Prophet and the believers who pray and give alms while prostrate to God . . . !" (5:58, 59).
Ibn Sinan narrated this incident in Sahih Al-Bukhari and Ibn Abbas narrated this story in Asbab Al-Nuzol by Imam Wahidi. All interpreters of Kanz Al-Umaal held the same opinion of the cause of the revelation of this. On a different occasion, the Prophet (S) told Imam Ali, "You are to me as Aaron was to Moses, but there is not Prophet after me". But perhaps the most outstanding occasion which sank into people's memories, is the Prophet's speech during his last pilgrimage.
Amongst a large congregation of Muslims he declared, "He whoever I am his master, Ali is his master too. O God assist whoever supports him and disgrace those who have enmity towards him". Indeed, whilst these are only a few of the quotations about Imam Ali, their consistency and the number and variety of people who confirmed the authenticity of the stories leaves no room for doubt that Imam Ali was chosen by God and His Prophet to be the ideological leader after the Prophet's departure.
Hence it can be safely concluded that Imam Ali's exclusion from his assigned duty marked the first major mistake. The inevitable consequences were a slow deviation which ended up in a turbulent stream of events, which no one was able to exercise control over. Abu Bakr's reign lasted approximately two years, which was an eventful epoch.
The dangers besieging the Muslims were so great that the very existence of the Muslim community was threatened, only being eliminated by the many sacrifices of the Muslim community. Umar ibn Al-Khattab was appointed by Abu Bakr as the Caliph, his rule being for ten years. His reign is particularly important because of the vast changes and events which took place during his time.
The conquest of vast areas brought enormous wealth to the Muslims, but the way this wealth was handled created complex problems, eventually forcing Umar to admit their grave consequences. Indeed, he tried to reform the laws but it was too late to act, for by that time he was murdered. Umar ibn Al-Khattab was the first person in charge of Muslim affairs to start uneven donation of provisions among Muslims.