While spirituality is certainly a factor in this fantastic book, I wouldn't say that there are examples of religion as such, and there is no talk of an afterlife in the aftermath of the death of Junior's sister or any of the other deaths that are referred to in the book.
As a native American, Junior participates in various cultural and spiritual rites, but at no point does he seem to associate himself with any religion or discuss belief in any higher power. I would argue that "that old time Indian spirit" was the closest thing that Junior knew to any religion.
Religion seems to be associated with the arrival of the white man, who, as Junior explains, brought with them Christianity and homophobia. A number of the characters who Junior describes are alcoholics who are prone to abusing children, and religion does not seem to be prevalent anywhere in this society. In fact, Junior expresses his pride in his grandmother for having rejected religion.
The Absolutely True Diary of a Part-Time...
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