It's a reference to Carrie, which I don't think you've read (yet). (I think the first King book you've read is Under the Dome, right?)
Anyway, it's a roundabout way to say that Carrie's mother has a God complex...and she's one scary broad. (She's a fervent religious nutjob, fruiter than Fruity Pebbles.)
I've probably seen the movie but it's sooooo long ago it's too vague now. I'm aware how the media enjoys making a mockery of certain things. I may have read other SK books since I've been reading for a long, long time so at this point I just don't remember.