That person had such strong faith that it healed him. First and foremost, a true love of music is needed. Because in reality it is the love that heals. Love is the highest power. Music cannot cope with being used.
True love knows no purpose.
And so we listen to music not in order to get something from it, but because of the music itself, because of the joy that being with music brings. Self-knowledge comes like an additional gift. Self-knowledge takes a lifetime. You become more and more aware, and music helps in this process. We need music, but not to fulfil our practical needs.