I just read a statement by Jackson Pollock in a book I was reading "Writing about Art". The statement was made in 1947 in a small magazine called "Possibilities". The author of the book was looking at what the artist had written to understand his art. Let me just quote what I found interesting , "When I am in my painting, I'm not aware of what I'm doing. It is only after a sort of get aquainted period that I see what I have been about." He is describing an unconscious working of the painting. It is this area where the spiritual world influences the physical world. In the case of Pollock, his alcoholism and other internal demons find expression in his paintings. I haven't yet seen one of his works up close in a museum, but just seeing them in a book you can sometimes sense the demonic influence.
Abstract expressionism gives amplification to the inner spiritual man through painting much the same way rock and roll does through music.