Islamic mysticism was formed in the second half of the second century of Hijri and developed at the same time as Islamic law. Sufis deny any influence of non-Islamic ideas in Sufism, but many evidences show that this thought was also influenced by other mysticisms. In this research, the elements of theoretical and practical mysticism, in the sayings and actions of mystics, based on two selected works of Tabaqat al-Sufiyyah by Khwaja Abdullah Ansari and Tazkira al-Awliya Attar, have been examined in the three religions of Islam, Christianity and Hinduism, in order to determine the similarities between Sufism. And Iranian mysticism exists with the ideas of Christianity and Buddhism, and in which cases is the suspicion of influence more. The evidence indicates that Christianity has been the closest non-Islamic schools to Islamic mysticism in terms of the development of the practical and outward part of mysticism, and Indian mysticism is more similar to Islamic mysticism than the theoretical and esoteric approach. The research method in this study is descriptive-analytical based on findings and studies and library sources. The results of this research indicate that although the Christian and Indian mystical schools have differences in their general approach to Islamic mysticism, there are similarities that indicate the effects of these mystical schools on the Islamic mystical school.