The Christian–Muslim engagement may be experienced at many levels: theological, political, cultural and global. The nature of Christian–Muslim relations in various states is also determining the scope of these states' international relations and alliances. Further Christianity experiences Islam as a religious and theological challenge. Since the earliest period in its history, the Islamic tradition has been conscious of the religious diversity of the human race and considered it an issue of importance. Yohannan Friedmann has reminded us that according to the Islamic tradition Islam is not only the historical religion and institutional framework that was brought into existence by the Muslim prophet Muhammad in the seventh century, but also the primordial religion of humankind, revealed to Adam at the time of his creation. It is thus that Christianity locates the challenge of Islam, not just as a historical encounter, which is of importance; or as a political force in the modern world; but also as a theological challenge. There is an intimacy to the Christian–Muslim encounter, which offers a familiarity, but allows for little theological commonality due to difference. Thus throughout the centuries since the rise of Islam, Muslim–Christian relations have revolved around this double axis of familiar, biblical appeal and strenuous, religious critique. It is this story that this book attempts to tell in a contemporary sense set against the global encounter between Christianity and Islam in the modern world.