Book excerpt: This book constitutes a comprehensive investigation of the life and teachings of one of the most famous Sufis of the Iranian world. Simnānī spent his early life as a courtier at the Ilkhanid Mongol court and was a cherished companion of the emperor Arghun. After a mystical experience on the battlefield, he turned his back on a life of luxury and became a Sufi. He advanced rapidly in his spiritual quest and soon became one of the most influential Sufi masters in Iran. Working primarily from the most Arabic and Persian manuscripts of Simnānī’s writings, the author has analyzed Simnānī's thinking to show the overall coherence of his world-view and to demonstrate the importance of his ideas to the development of Islamic mysticism. Along with this analysis, the author provides a detailed account of Simnānī's life and times, as well as a systematic description of Simnānī's instructions for Sufi practioners of all levels.