How superficial was the adherence of numbers of the Arab tribes to the faith of Islam may be judged from the widespread apostasy that followed immediately on the death of the Prophet. Their acceptance of Islam would seem to have been often dictated more by considerations of political expediency, and was more frequently a bargain struck under pressure of violence than the outcome of any enthusiasm or spiritual awakening. They allowed themselves to be swept into the stream of what had now become a great national movement, and we miss the fervent zeal of the early converts in the cool, calculating attitude of those who came in after the fall of Mecca. But even from among these must have come many to swell the ranks of the true believers animated with a genuine zeal for the faith, and ready, as we have seen, to give their lives in the effort to preach it to their brethren. “These men were the true moral heirs of the Prophet, the future apostles of Islam, the faithful trustees of all that Muḥammad had revealed unto the men of God. Into these men, through their constant contact with the Prophet and their devotion to him, there had really entered a new mode of thought and feeling, loftier and more civilised than any they had known before; they had really changed for the better from every point of view, and later on as statesmen and generals, in the most difficult moments of the war of conquest they gave magnificent and undeniable proof that the ideas and the doctrines of Muḥammad had been seed cast on fruitful soil, and had produced a body of men of the very highest worth. They were the depositaries of the sacred text of the Qurʼān, which they alone knew by heart; they were the jealous guardians of the memory of every word and bidding of the Prophet, the trustees of the moral heritage of Muḥammad. These men formed the venerable stock of Islam from whom one day was to spring the noble band of the first jurists, theologians and traditionists of Muslim society.” [43] But for such men as these, so vast a movement could not have held together, much less have recovered the shock given it by the death of the founder. For it must not be forgotten how distinctly Islam was a new movement in heathen Arabia, and how diametrically opposed were the ideals of the two societies. [44] For the introduction of Islam into Arab society did not imply merely the sweeping away of a few barbarous and inhuman practices, but a complete reversal of the pre-existing ideals of life.