In the 10th century, under the weight of tradition and consensus, Muslim scholars (ulama) proclaimed “the gates of ijtihad (individual judgment)” closed; new concepts and interpretations could no longer stand on their own but had to be legitimized by tradition. This proscription notwithstanding, ijtihad continues today, though not on the scale of the first centuries of Islam. Meanwhile, the applicability of sharia, or Islamic law, is a subject of much strife in a number of Muslim lands, which have seen challenges to entrenched governments by movements carrying the banner of Islam (or their interpretation of it).

The Sufis are a mystical movement within Islam, stressing the goal of unity with God. They are organized in orders, with a clear hierarchy from master to disciple. Sufi sheiks (masters) are reputed to perform miracles, and their tombs are popular pilgrimage destinations. The term “whirling dervish” derives from the joyous spinning and dancing at Sufi festivals.