The Persian Mystics: Jalalu'd-Din Rumi, Wisdom Of The East
by F. Hadland Davis
...the Mohammedans Sufiism, or Persian mysticism, is known as tasawwuf. The word Sufi is derived from sui, meaning" wool." When a little Persian sect at the end of the eighth century A.D. broke away from the orthodox ~iuslhn religion, and struck out on an independent path, they ignored costly robes and worldly ostentation, and clad themselves in a white wool garment. Hence they were known as "wool wearers," or Sufis. Prof. Edward G. Browne gives four theories in regard to the origin of Sufiism...