"Gospel music is about a step of faith, which is a whole different concept. The idea is that you step into a world where, if you like, the kingdom has come. You step into it, and you affirm that. You step into that and you sing!
You know, people singing gospel music, they crowded into the churches from the ghettos, to make that 'Joshua fit the battle of Jericho/And the walls came tumbling down' step of faith. In their real life, they were living in leaky, rainy conditions, they were living in a sewer. So that's not the truth of their own experience. The blues is the truth of their own experience, therefore closer to this idea of 'knowing the truth and the truth shall set you free.'
In the Psalms of David, there is this powerful wailing against God. You know, 'You call yourself God!' and 'Where are you when I need you?' The Psalms of David are the blues, and I get great comfort from that."