Perhaps there is no other religion in the history of mankind that has relied so heavily on promotions to support its causes as much as Islam. The religion, which was inaugurated with the words read, teach and write in an era when only the privileged were literate, is no stranger to the professional use of promotional means in the propagation of its principles. Muslims, all of whom are commanded to assume the role of holy marketers according to their own individual capacities, employed the word in its various forms – spoken, sung, implied, lived and written – in order to attract the public to embrace the new faith. The Quran teaches that all invitations must be extended with kindness by those who are knowledgeable. Cultural differences and their effects on the success of promotions are also acknowledged in the Quran. Islam's approach to promotions for societal and other causes stresses the importance of gradualism and persistence.