Muhammad’s continuing success gradually impinged on the Quraysh in Mecca. Some defected and joined his community. His marriage to a Quraysh woman provided him with a useful go-between. In 628 he and his followers tried to make an Islamized hajj but were forestalled by the Meccans. At Al-Ḥudaybiyah, outside Mecca, Muhammad granted a 10-year truce on the condition that the Meccans would allow a Muslim pilgrimage the next year. Even at this point, however, Muhammad’s control over his followers had its limits; his more zealous followers agreed to the pact only after much persuasion. As in all instances of charismatic leadership, persisting loyalty was correlated with continuing success. In the next year the Meccans allowed a Muslim hajj; and in the next, 630, the Muslims occupied Mecca without a struggle. Muhammad began to receive deputations from many parts of Arabia. By his death in 632 he was ruler of virtually all of it.

The Meccan Quraysh were allowed to become Muslims without shame. In fact, they quickly became assimilated to the actual muhājirūn, even though they had not emigrated to Yathrib themselves. Ironically, in defeat they had accomplished much more than they would have had they achieved victory: the centralization of all of Arabia around their polity and their shrine, the Kaʿbah, which had been emptied of its idols to be filled with an infinitely greater invisible power.

Because intergroup conflict was banned to all members of the ummah on the basis of their shared loyalty to the emissary of a single higher authority, the limitations of the Meccan concept of ḥaram, according to which the city quarterly became a safe haven, could be overcome. The broader solidarity that Muhammad had begun to build was stabilized only after his death, and this was achieved, paradoxically, by some of the same people who had initially opposed him. In the next two years one of his most significant legacies became apparent: the willingness and ability of his closest supporters to sustain the ideal and the reality of one Muslim community under one leader, even in the face of significant opposition. When Muhammad died, two vital sources of his authority ended—ongoing revelation and his unique ability to exemplify his messages on a daily basis. A leader capable of keeping revelation alive might have had the best chance of inheriting his movement, but no Muslim claimed messengership, nor had Muhammad unequivocally designated any other type of successor. The anṣār, his early supporters in Medina, moved to elect their own leader, leaving the muhājirūn to choose theirs, but a small number of muhājirūn managed to impose one of their own over the whole. That man was Abū Bakr, one of Muhammad’s earliest followers and the father of his favourite wife, ʿĀʾishah. The title Abū Bakr took, khalīfah (caliph), meaning deputy or successor, echoed revealed references to those who assist major leaders and even God himself. To khalīfah he appended rasūl Allāh, so that his authority was based on his assistance to Muhammad as messenger of God.

Abū Bakr’s succession

Abū Bakr soon confronted two new threats: the secession of many of the tribes that had joined the ummah after 630 and the appearance among them of other prophet figures who claimed continuing guidance from God. In withdrawing, the tribes appear to have been able to distinguish loyalty to Muhammad from full acceptance of the uniqueness and permanence of his message. The appearance of other prophets illustrates a general phenomenon in the history of religion: the volatility of revelation as a source of authority. When successfully claimed, it has almost no competitor; once opened, it is difficult to close; and, if it cannot be contained and focused at the appropriate moment, its power disperses. Jews and Christians had responded to this dilemma in their own ways; now it was the turn of the Muslims, whose future was dramatically affected by Abū Bakr’s response. He put an end to revelation with a combination of military force and coherent rhetoric. He defined withdrawal from Muhammad’s coalition as ingratitude to or denial of God (the concept of kufr); thus he gave secession (riddah) cosmic significance as an act of apostasy punishable, according to God’s revealed messages to Muhammad, by death. He declared that the secessionists had become Muslims, and thus servants of God, by joining Muhammad; they were not free not to be Muslims, nor could they be Muslims, and thus loyal to God, under any leader whose legitimacy did not derive from Muhammad. Finally, he declared Muhammad to be the last prophet God would send, relying on a reference to Muhammad in one of the revealed messages as khatm al-anbiyāʾ (“seal of the prophets”). In his ability to interpret the events of his reign from the perspective of Islam, Abū Bakr demonstrated the power of the new conceptual vocabulary Muhammad had introduced.

Had Abū Bakr not asserted the independence and uniqueness of Islam, the movement he had inherited could have been splintered or absorbed by other monotheistic communities or by new Islam-like movements led by other tribal figures. Moreover, had he not quickly made the ban on secession and intergroup conflict yield material success, his chances for survival would have been very slim, because Arabia’s resources could not support his state. To provide an adequate fiscal base, Abū Bakr enlarged impulses present in pre-Islamic Mecca and in the ummah. At his death he was beginning to turn his followers to raiding non-Muslims in the only direction where that was possible, the north. Migration into Syria and Iraq already had a long history; Arabs, both migratory and settled, were already present there. Indeed, some of them were already launching raids when ʿUmar I, Abū Bakr’s acknowledged successor, assumed the caliphate in 634. The ability of the Medinan state to absorb random action into a relatively centralized movement of expansion testifies to the strength of the new ideological and administrative patterns inherent in the concept of ummah.

The fusion of two once separable phenomena, membership in Muhammad’s community and faith in Islam—the mundane and the spiritual—would become one of Islam’s most distinctive features. Becoming and being Muslim always involved doing more than it involved believing. On balance, Muslims have always favoured orthopraxy (correctness of practice) over orthodoxy (correctness of doctrine). Being Muslim has always meant making a commitment to a set of behavioral patterns because they reflect the right orientation to God. Where choices were later posed, they were posed not in terms of religion and politics, or church and state, but between living in the world the right way or the wrong way. Just as classical Islamicate languages developed no equivalents for the words religion and politics, modern European languages have developed no adequate terms to capture the choices as Muslims have posed them.