Once a classical musician, Inayat Khan let go of his greatest attachment – his musical career – to become a Sufi Master, as is the tradition in Sufism. Immersing himself in the Sufi ideology, he found a link between his former life as a musician and his new journey along the spiritual path. Khan saw harmony as the "music of the spheres" which linked all mankind and had the ability to transcend one's spiritual awareness. Khan's most influential, "The Music of Life", is a collection of Khan's teachings on sound, presenting his vision of the harmony which encompasses every aspect of our lives. He explores the science of breath, the law of rhythm, the creative process, and both the healing power and psychological influence of music and sound. From "The Music of Life":