When John Coltrane began, his tone wasn't strong, his technical grasp was unsure, and he borrowed a lot from his early r&b influences. It took quite a while before he emerged as a mature man, let alone a mature musician. But in 1955 Coltrane joined Miles Davis's group, and then he apprenticed with Thelonious Monk. And, along with maturing musically, he experienced a great spiritual awakening. Coltrane's last decade or so saw him take one leap forward after another - mastering all his teachers' ideas and then moving to a level beyond that of any other saxophonist. For those journeys he formed his classic quartet, which eventually evolved into a completely different second group. The repertoire of each has had a hold, spiritual as well as artistic, not just on musicians in all fields but on listeners in all walks of life.