I think the search for a sense of belonging is an important part of this story. It's a coming of age story, and a big part of this is understanding our childhood, the adults, and in this case religion. Here is a link to a list of themes for this book.
I haven't read the novel, but look for specific phrases that clarify Rodriguez' sense of belonging (in other words; I feel comfortable here, accepted, wanted).
By any chance are you doing the NSW HSC English Stage 6 course? Belonging is one of the universal topics.