Naturally this ecclesiasticism which dominated the whole of life, was bound to assert itself in state organisation. An abhorrence of the state, so far as it was independent of religion, a feeling unknown in the ancient world, pervades both Christianity and Muhammedanism, Christianity first struggled to secure recognition in the state and afterwards fought with the state for predominance. Islam and the state were at first identical: in its spiritual leaders it was soon separated from the state. Its idea of a divine polity was elaborated to the smallest details, but remained a theory which never became practice. Yet this ideal retained such strength that every Muhammedan usurper was careful to secure his investiture by the Caliph, the nominal leader of this ecclesiastical state, even if force were necessary to attain his object. For instance, Saladin was absolutely independent of the nominal Caliph in Bagdad, but could not feel that his position was secure until he had obtained his sultan's patent from the Caliph. Only then did his supremacy rest upon a religious basis and he was not regarded by popular opinion as a legitimate monarch until this ceremony had been performed. This theory corresponds with constitutional ideals essentially Christian. "The tyranny," wrote Innocent IV to the Emperor Frederick II, "which was once generally exercised throughout the world, was resigned into the hands of the Church by Constantine, who then received as an honourable gift from the proper source that which he had formerly held and exercised unrighteously." The long struggle between Church and State in this matter is well known. In this struggle the rising power of Islam had adopted a similar attitude. The great abhorrence of a secular "monarchy" in opposition to a religious caliphate, as expressed both by the dicta of tradition and by the Abbassid historians, was inspired, in my opinion, by Christian dislike of a divorce between Church and State. The phenomenon might be explained without reference to external influence, but if the whole process be considered in connection, Christian influence seems more than probable.