It is interesting to note that out of three desert-based religions, Christianity and Islam are Missionary in nature. The third one i.e. Judaism is non-Missionary like river-based religion of Hinduism (Brahmanism). Both Christianity and Islam originated from respective single personality (Jesus and Muhammad) but Judaism has more than one prophet who came over a long period of time. Hinduism also originated from multiple personalities. This singleness of prophet or originator had made Christianity and Islam Missionary. Similarly the river-based religion of Buddhism is also Missionary in nature.
Missionary endeavour was also necessary in case of Islam, Christianity and Buddhism as these came into being at sudden point of time against the strong current of the then existing and flourishing religions. Buddhism is intrinsically non-violent in essence and spirit. So, it took the recourse of persuasion, advice and exemplification of life style by Buddha and Buddhist monks to induct people into its fold. Christianity, though based on love and compassion, had seen rough and tough approach particularly in middle age when Popes and Christian priests were ruthless like Mafia bosses. But Islam was a different ball game from the beginning. Firstly Muhammad faced ridicule and hatred for a very prolong period of time unlike Jesus (who died at around 35 years of age). Secondly, initial success was achieved (through wars) in case of Islam (unlike Christianity) during the life time of Muhammad who died at 62 years of age.
The 100 odd wars fought by Muhammad and many Qur’anic verses advocating the use of force for the expansion of religion was internalized within Islam at initial phase. This striving course of Islam during Muhammad’s life became its driving force after his death. The raw strength of united Arab Muslims and latter non-Arab Muslims expanded into a huge Islamic kingdom larger than the size of biggest Roman Empire within one hundred years after Muhammad’s death. And that was impossible without violence.
Sufism, the mystic and spiritualist Islam, came into being much latter and mainly due to the influence of non-Arab Muslims. However, many Sufi saints also fought wars with swords along with their followers in isolation or shoulder to shoulder with Muslim kings for expansion of kingdom and religion. The great Sufi saint Shah Jalal of Sylhet was no exception. Islam had justified violence as a means of religio-political expansion from its nascent stage.
Mongols invaded Islamic empire of Central Asia, Persia and Afghanistan during first quarter of thirteenth century. Mongol hoards were animists and devastated the Islamic Empire. But in subsequent decades Mongols accepted Islam in a competing situation with other two Missionary religions, i.e. Christianity and Buddhism. When Islamic Empire was in danger due to plunder by the Mongol barbarians, the Sufism brought Islam to newer places like Bengal, Malaya and some parts of Indian sub-continent at the same time.
This dichotomy of violence and mysticism had given Islam much maneuvering power to propagate Islam, as it can justify both for the same purpose. But problem began when in latter part of twentieth century hard core Muslims started disowning Sufism and resorted to terrorism. The only face left with Islam was of violence. For most non-Muslims now, Islam is synonymous with a religion of violence.