***t's not anti-christian, it's religiously neutral.***
There is not such thing as "religiously neutral".
Yes there is. The vast majority of entertainment is religiously neutral, taking sides in religion is bad for business, smart authors tread there very lightly or preferably not at all. HP has nothing to do with religion, it's just a fantasy story in an imaginary world that has a different concept for magic than we do. The closest you get to religion in HP is that every school year has a Christmas break repleat with the normal trapping of Christmas out here in reality (tree, presents, fattening food). That's about all you get.