Tilman Nagel examines the beginnings of Islam and the rise of Mohammed:

Only amidst numerous errors and confusions was it clarified during the decades following Mohammed’s death just what the “straight path” consisted of in the midst of all of life’s vicissitudes: the deceased Mohammed then began a second life, so to speak, with authoritative statements on all and sundry being attributed to him. Here is the origin of the Muslim image of the Prophet as the all-knowing and all-competent conveyor of divine, eternally valid law. This image brought about a certain biographical stylisation, one regarded by Muslims as being the historical “truth”. Scholars need to distinguish this image as clearly as possible from the image resulting from the source analysis referred to here on the basis of several examples; they must examine the question of how and under which historical circumstances this stylisation was formed. There is certainly no shortage of source materials to which we can turn in pursuing this task.

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