One of the most widely read Sufi treatises in Arabic, the Risala defines classical Sufism through the use of quotations from the Qur?an, the Prophetic Traditions and reference to the exemplary behaviour for the ascetics and saints. Al-Qushayri illustrates the principles of Sufism with tales and sayings of the first generation of Muslims and of the Prophet?s contemporaries in the 5/11th century. Readers are given a rich account of what Sufism as a way of life implied for the early Muslims.