Sufism
Islam prohibits monasticism which is referred to in the Quran as "an invention". However, the term "Sufi" is applied to Muslim mystics who, as a means of achieving union with Allah, adopted ascetic practices including wearing a garment made of coarse wool called "sf". The term "Sufism" comes from "sf" meaning the person, who wears "sf". But in the course of time, sufi has come to designate all Muslim believers in mystic union.
In the roots of sufi philosophy there are influences of neoplatonist and other philosophies. Many of the practices of Orthodox Christian hermits and desert-dwellers were imitated in Sufism's growth in the center of the former-Christian lands of the Middle East. Ascetic practices within the sufi philosophy were also associated with Buddhism. The notion of purification (cleaning one's soul from all evil things and trying to reach Nirvana and to become immortal in Nirvana) plays an important role in Buddhism. The same idea shows itself in the belief of "fanaa" (union with God) in Sufi philosophy.
Read more about this topic: Monastery