[Sir Sultan Muhammed Shah, Aga Khan III (1877-1957) was a Muslim leader and statesman. He was the 48th Imam of the Ismaili community, the first president of the All-India Muslim League, and the President of the League of Nations from 1937-38. The following excerpt is from a chapter entitled “Islam, the Religion of My Ancestors” from his book, World Enough and Time: The Memoirs of Aga Khan (1954).]
According to the Sunni school, the majority of Muslims, the Prophet’s religious authority came to an end at his death, and he appointed no successor to his secular authority. According to Sunni teaching, the faithful, the companions of the Prophet, the believers, elected Abu Bakr as his successor and his Khalif; but Abu Bakr assumed only the civil and secular power. No one had the authority to succeed to the religious supremacy, which depend on direct Divine inspiration, because the Prophet Mohammed and the Koran declared definitely that he was the final messenger of God, the Absolute. Thus, say the Sunnis, it was impossible to constitute an authority similar to that of the Papacy; it remained for the Faithful to interpret the Koran, the example and the sayings of the Prophet, not only in order to understand Islam but to ensure its development throughout the centuries. …
The Sunnis are the people of the Sunna or tradition. Their Kalama or profession of faith is “There is no God but God and Mohammed is the Apostle of God.” To this the Shias add: “And Ali, the companion of Mohammed, is the Vicar of God.” Etymologically the word “Shia” means either a stream or a section.
The Prophet died without appointing a Khalif or successor. The Shia school of thought maintains that although direct Divine inspiration ceased at the Prophet’s death, the need of Divine guidance continued and this could not be left merely to millions of mortal men, subject to the whims and gust of passion and material necessity, capable of being momentarily but tragically misled by greed, by oratory, or by the sudden desire for material advantage. These dangers were manifest in the period immediately following our Holy Prophet’s death. Mohammed had been, as I have shown, both a temporal and a spiritual sovereign. The Khalif or successor of the Prophet was to succeed him in both these capacities; he was to be both Emir-al-Momenin or “Commander of the true believers” and Imam-al-Muslimin or “spiritual chief of the devout.” Perhaps an analogy from the Latin, Western world will make this clearer: he would be Supreme Pontiff as well as Imperator or temporal ruler.
Ali, the Prophet’s cousin and son-in-law, the husband of his beloved and only surviving child, Fatimah, his first convert, his bold champion in many a war, who the Prophet in his lifetime said would be to him as Aaron was to Moses, his brother and right-hand man, in the veins of whose descendants the Prophet’s own blood would flow, appeared destined to be that true successor; and such had been the general expectation of Islam. The Shias have therefore always held that after the Prophet’s death, Divine power, guidance and leadership manifested themselves in Hazrat Ali as the first Imam or spiritual chief of the devout. The Sunnis, however, consider him the fourth in the succession of Khalifs to temporal power.
The Imam is thus the successor of the Prophet in his religious capacity; he is the man who must be obeyed and who dwells among those from whom he commands spiritual obedience. The Sunnis have always held that this authority is merely temporal and secular, and is exerted only in the political sphere; they believe therefore that it appertains to any lawfully constituted political head of a state, to a governor or to the president of a republic. The Shias say that this authority is all-pervading and is concerned with spiritual matters also, that it is transferred by inherited right to the Prophet’s successors of his blood.