He wasn't an unthinking fundamentalist, though. Mr. Am himself mentions how old scientists think the universe was, and it's pretty close to what scientists DID think at the time. Nor does Mr. Am seem to be mocking THAT part of their knowledge---just that he could tell them a lot more. So he's a sophisticated believer, not a literalist...
Still creepy, though. It's sort of like the dwarves who worked for God in TIME BANDITS...