"The Mysticism of Sound and Music" by Hazrat Inayat Khan

The first teacher to bring Islamic mysticism to the West presents music’s divine nature and its connection to our daily lives in this poetic classic of Sufi literature
 
Music, according to Sufi teaching, is really a small expression of the overwhelming and perfect harmony of the whole universe—and that is the secret of its amazing power to move us. The Indian Sufi master Hazrat Inayat Khan (1882–1927), the first teacher to bring the Islamic mystical tradition to the West, was an accomplished musician himself. His lucid exposition of music's divine nature has become a modern classic, beloved not only by those interested in Sufism but by musicians of all kinds.