Hell, according to the Harry Potter books, even resurrection is possible, and that's supposed to be a trick limited to Jesus only (and his close pal, that one time). Oh, and there's a magical stone that will grant you eternal life.
Therefore, anyone who both knows about magic and believes in the Bible is in for a huge theological dilemma: Can you continue having faith in God if it turns out He was wrong about a lot of stuff? This would be a huge blow to anyone's beliefs, but the books/movies never touch on the subject.
"And risk these sales?"
Now, in the Harry Potter world, most normal people don't know about wizards, but a lot of them do, including some important political figures, like Britain's prime minister. Many others witness magic firsthand when their seemingly normal kids start developing powers.