That's one half of it, but there is also a story half here as well. The religion in this game has a few notable issues, the main one being they are purely responsible for the slavery of elves. Corrupting Autumn religiously also implies changing her mind about elves so that she sees them more like people than animals. (which has never been a huge problem for her)
Religious corruption in this game has nothing to do with God, but religion specifically, and how humans can corrupt it. Humans aren't perfect, so issues can come up.