The "sharp" Christian is Creationist douchetard Ken Ham. The man who coined the phrased "looking at the world through Biblical glasses." He is about the worst kind of dribbling, moronic apologist out there.
Yes, this is the "were you there" guy, though to be fair, that's pretty much the refuge of most creationists these days.
He also claims he has "scientific" evidence that pretty all science is wrong. I'm not sure how that works.
Infidel, heathen, blasphemer....I think the latest buzzword is "secular" with a tone of derision. It can cover all sorts of things from people to laws.