In proportion as the lot of the conquered peoples became harder to bear, the more irresistible was the temptation to free themselves from their miseries, by the words, “There is no god but God: Muḥammad is the Apostle of God.” When the state was in need of money—as was increasingly the case—the subject races were more and more burdened with taxes, so that the condition of the non-Muslims was constantly growing more unendurable, and conversions to Islam increased in the same proportion. The dreary record of scandals, with which the pages of the Christian historians of this later period are filled, would suggest that the Christian Churches had failed to develop a moral fibre strong enough to endure the stress of adverse conditions, and when persecution came, the reason for the defection that followed might—as the historian of the Nestorian Church suggests [185]—be sought for in the prevailing negligence in the performance of religious duties and the evil life of the clergy. Further causes that contributed to the decrease of the Christian population may be found in the fact that the children of the numerous Christian captive women who were carried off to the harems of the Muslims had to be brought up in the religion of their fathers, and in the frequent temptation that was offered to the Christian slave by an indulgent master, of purchasing his freedom at the price of conversion to Islam. But of any organised attempt to force the acceptance of Islam on the non-Muslim population, or of any systematic persecution intended to stamp out the Christian religion, we hear nothing. Had the caliphs chosen to adopt either course of action, they might have swept away Christianity as easily as Ferdinand and Isabella drove Islam out of Spain, or Louis XIV made Protestantism penal in France, or the Jews were kept out of England for 350 years. The Eastern Churches in Asia were entirely cut off from communion with the rest of Christendom, throughout which no one would have been found to lift a finger on their behalf, as heretical communions. So that the very survival of these Churches to the present day is a strong proof of the generally tolerant attitude of the Muhammadan governments towards them. [186]