The origins of Sufism (taṣawwuf in Arabic), or Islamic mysticism, appear clearly in the spiritual practise of the Prophet Muhammad in seventh-century Arabia (Massignon 1954, Lings 1993). Sufism's key contemplative discipline, remembrance of God (dhikr), was practiced continually by the Prophet and is alluded to in fifteen verses of the Qur'ān. From this practise the Sufis developed an entire science of invocations and supplications (adhkār) designed to cultivate the heart, refine the soul, and elevate ordinary human consciousness into awareness of the ever-immanent divinity (Chittick 1987). There are nonetheless a number of formative influences on early Sufism that are extraneous to early Qur'ānic spirituality. Michael Sells (1996) has demonstrated that the heritage of pre-Islamic poetry provided numerous subthemes (for example, drunkenness, love-madness, perpetual wandering, the secret shared between lover and beloved) for later Sufi literature and poetry. Scholars such as D. Miguel Asin Palacios, Tor Andrae, Duncan Macdonald...