Abstract
This article analyses the impact of the ideological function of Islam on its religious content during the first centuries following its genesis. The author shows first that the new religion was in fact a social protest against the upper social groups of Medina, the Christians and the Jews. The reaction against this socio-religious movement provoked armed conflicts and finally, after the death of the founder, the establishment of a kingdom in which the religious leaders had also the political power. The fact that the Islamic religion became the ideology, was at the origin of a necessity to produce new religious meanings which were able to justify the political power. It explains the development of new religious roles growind together with the secularisation of the political ones. The Koran was the first written production of those theo logians in which they included, in an integrated system, the beliefs preached by the founder and their own production.