God but to worship and adore him as a protector. Any kind of idolatry is condemned in Islam. () As a result, Muslims hold that for someone to worship any other gods or deities other than Allah ( (polytheism)) is a sin that will lead to separation from Allah. Muslims believe that Allah sent the Qur'an to bring peace and harmony to humanity through Islam (submission to Allah). Muhammad's worldwide mission was to establish universal peace under the . The ensured security of the lives and property of non-Muslims under the system. This status was originally only made available to non-Muslims who were "People of the Book" (Christians, Jews, and Sabians (commonly identified with the Mandaeans)), but was later extended to include Zoroastrians, Sikhs, Hindus, and Buddhists. had more rights than other non-Muslim religious subjects, but often fewer legal and social rights than Muslims. Some Muslims, however, disagree, and hold that adherents of these faiths cannot be . enjoyed some freedoms under the state founded by Muhammad and could practice their religious rituals according to their faith and beliefs. Non-Muslims who were not classified as "people of the book," for example practitioners of the pre-Muslim indigenous Arabian religions, had few or no rights in Muslim society. Muslims and Muslim theologians attend at many interfaith dialogues, for example at the Parliament of the World's Religions with whom in 1993 also Muslim theologians signed the Declaration Toward a Global Ethic. Religious persecution is also prohibited, although religious persecution in Muslim majority states has occurred, especially during periods of cruel rulers and general economic hardships. Pre-Islamic religious minorities continue to exist in some of their native countries, although only as marginal percentages of the overall population. Over the centuries, several known religious debates, and polemical works did exist in various Muslim countries between various Muslim sects, as well as between Muslims and non-Muslims. Many of these works survive today, and make for some very interesting reading in the apologetics genre. Only when such debates spilled over to the unlearned masses, and thus causing scandals and civil strife, did rulers intervene to restore order and pacify the public outcry on the perceived attack on their beliefs. As for sects within Islam, history shows a variable pattern. Various sects became intolerant when gaining favour with the rulers, and often work to oppress or eliminate rival sects, for example, the contemporary persecution of Muslim minorities in