Parents trouble accepting, resources to help them?

I recently came out to my parents. My mother was extremely accepting and happy for me, but my father is having a bit more of a difficult time with it. He has barely spoken to me since I told them. I think he's taking a long time to process it and has made comments to my mother that he feels like he has turned out to be a bad father or has somehow failed me as a father. I think he is also upset because he is very religious and is conflicted with what his faith says. What resources do you suggest for him to help be more accepting of me and realize that me being gay is something far beyond his control?