I'm not usually one to laugh at religious beliefs, but... really?
First off, I'm not sure I understand the problem Christians have with this. Mencken described puritanism as "the haunting fear that someone, somewhere, might be happy." This falls into that category. Second, and more importantly, who the hell would wear that shirt in public? Third, taking up Balko's point, they'd probably have to take that shirt off and put an "ex-liar" shirt on right afterwards.