Although I'm enthusiastic about him, I recognize that he's not an author for everybody. I think that many people just don't "get" him. Also, he writes often in first-person, which I love, but others dislike. I notice that in American Prayer his voice is more precise, almost formal, than in his other stories, and every single word seems carefully chosen. This is because this particular story is partially about precision in language and intention, and it's perfectly suited.
He's lived an interesting life. He coped with family violence by learning to box, and then as an adult became active in changing boxing laws to protect boxers. He left home at 16, took a freighter overseas, and spent many years living in southeast asia, the middle east, south and central america, the caribbean, and sometimes took disreputable jobs to survive, so he has a breadth of experience few others have. He lives large, to the benefit of his readers.
He's outspoken about political concerns that result in social injustice, and many of the settings are just down and dirty. He did an in-depth article on hobos, and lived "on the rails" for awhile to learn more. His book, Two Trains resulted from those experiences.
He writes short fiction, and he's worth a slower reading than some people are willing to give.