Have you read this novel? I suspect you could find it a good work of literary fiction. There's this guy, right? And he's got a Mission, and this Mission was given to him by god, and there's this thing that people in his culture do, and this thing is going out into the desert and getting purified. And this guy, he's going to do it Right, and there are other people out there, because it's a Thing to go out and do this thing for 40 days, and, you know, 40 days in the desert takes some planning, and this guy's Plan isn't the ordinary sort of plan most of the people who are going to do this make. And, you know, the other people out there are really curious about this guy, and how it's going for him.
Jim Crace is really good at naturalistic descriptions of natural things in a way that carries meaningful weight.
Get it from your library, or buy it used, yeah?