JK Rowling skrev historier i den verkliga världen, bara med magi. Vår värld redan har religioner, och hon såg inget behov av att uppfinna mer. Dessutom var hennes koncept av magi sekulärt; magi är i själva verket en form av vetenskap, det beror inte på aktiv ingripande av en gud eller gudar. Hon har sagt att Wicca inte visas i böckerna av den anledningen:
Responding to questions as to why Wicca, a modern pagan religion that also uses the words “witch” and “wizard” to describe its members, was not represented at Hogwarts, Rowling said: “It's a different concept of magic to the one laid out in the books, so I don't really see how they can co-exist.”
Rowling identifierar sig som en kristen, och ser böckerna som att utforska kristna teman offer och uppståndelse:
"To me, the religious parallels have always been obvious," Rowling said. "But I never wanted to talk too openly about it because I thought it might show people who just wanted the story where we were going."
At the end of her latest and final installment in the series, there are specific references to Christianity and themes of life after death and resurrection.
At one point Harry visits his parents' graves and finds two biblical passages inscribed on their tombstones. "They are very British books, so on a very practical note, Harry was going to find biblical quotations on tombstones," she said.
"But I think those two particular quotations he finds on the tombstones ...they sum up, they almost epitomise, the whole series."
Att lägga till fiktiva religioner skulle bara avleda sig från detta element i hennes skrivande.