Mysticism generally means intuitive spiritual revelation and the belief that direct communion with God is achievable through human intuition. Almost all religions have their spiritual and mystical stances. So do Christianity and Islam, which are compared in the present study. In spite of the fact that these two religious traditions vary in some context yet in Mystical domain, both bear strong resemblances. Mystics of both faiths teach and preach the similar virtues of love, peace, unity and mutuality. The Holy books of both refer explicitly or inexplicitly to spirituality and to those have been blessed by spiritual insightfulness. Saint Paul was the first great Christian Mystic. However, Jesus Christ is called the founder of Christian mysticism. Christian mysticism is indebted to the Jewish heritage and Greek thought, especially to the writings of Dionysius, the Areopagite. John Scotus Erigena translated these writings and introduced them into Western Europe, whereas Saint Augustine further developed it. During the Dark Ages, mystical approaches in Christianity were criticized due to their emphasis on ritualistic purity and theological nature of Christian empire. Yet mysticism spread widely in that period as for the first time Christian mystics were given acknowledgement instead of persecution. In the main time, Islamic world saw an uninhibited growth of mysticism/ Sufism where we find Persian mystics like Al-Hallaj in about 900 A.D and later on Al-Ghazali, the Islamic philosopher. In 13th century Ibn al Arabi, Jalal al Din Rumi described desire of human soul for God. Sufism owes wholly to Prophetic model. In Sufism we find well-established Sufi orders and Sufi terminologies which are almost invisible in Christian mysticism. Islamic spiritualism exerted much influence on Europe and almost a century later, we find notable Christian mystics for example, Thomas a Kempis. Later on, there emerged Christian mystics in England and America. Since then a history of mystical parallelism came into observance. The present study has explored the history of mysticism to determine the mutual impact of various mystical schools in Christianity and Islam to allow a comparative and effective exploration of the fundamental doctrines. However, metaphysical experiences and contributions from both sides clearly bring to light certain contrasts as well which emphasize originality of Sufism. International scenario of the global village brought to light theory of clash of civilizations which compelled the scholars of the major religious doctrines to think about inter-faith dialogue. Thus the academia developed an interest in the pluralist world view and it was gradually realized that the Sufis or the men of esoteric learning were best suited for the task of Universal peace and harmony.