Religion in the music system
Spirituality in Jazz
Duke Ellington
Read the following brief biography
Read this NPR story, and listen to the audio.
Browse his official web site, as you wish.
John Coltrane
Optionally, browse this article about Coltrane's most famous composition, A Love Supreme, by noted jazz scholar and Coltrane biographer Lewis Porter.
Sun Ra
Sun Ra: From Ephrata (F-Ra-Ta) to Arkestra by David W. Stowe
Jazzmen: Diz and Sun Ra by Amiri Baraka
Mary Lou Williams
Browse as much as possible in Mary Lou Williams' website, including all of the section entitled Religious Conversion
Browse an interview with Mary Lou Williams