I may be reading into it a little too much, but considering the band members are christians and all the spiritual lines ("song so divine", "constant war inside my soul", etc.), I think Joe's using music as a metaphor for faith; how nothing is so beautiful or comforting than the quiet, but constant, rhythm and melody of faith. No matter how dark the situation may seem, there is a way because of that music which gives purpose to those who listen and relish in it.
I may be reading into it a little too much, but considering the band members are christians and all the spiritual lines ("song so divine", "constant war inside my soul", etc.), I think Joe's using music as a metaphor for faith; how nothing is so beautiful or comforting than the quiet, but constant, rhythm and melody of faith. No matter how dark the situation may seem, there is a way because of that music which gives purpose to those who listen and relish in it.