"Neither the sword nor the work of an ecclesiastical order can account for Islam's continuous gains in new following. The phenomenon of growth, therefore, must be attributed in the last analysis to its powers of appeal and ability to meet the spiritual and material needs of peoples adhering to cultures totally alien to the founders, the desert Arabians, but at a level of religious and sociopolitical development familiar to them at the time of their conversion. Continued growth can be explained also in terms of Islam's willingness to tolerate views and practices stemming from alien cultural norms brought into Islam by the converts which a more rigid system of religion would not countenance. Flexibility at this, the crucial stage, of conversion is an important factor contributing to Islam's success. What would ordinarily be deemed heretical at the instance of conversion inevitably drifts or is lured towards orthodoxy. The spread of Islam into Southeast Asia and sub-Saharan Africa presents a vivid example of its dynamism while its ability to survive in areas once dominated by communism is a testimony to its remarkable resilience."