Just invite him in and convert him to athiesm.

When you're a polite person it's hard to get rid of these guys... I suggest rigging your doormat as a trap door, leading to an alligator pit, activated by a button on your wall.

only way I ill join a religion is if they procure a vegan pepperoni pizza, extra meat, for it is an act of freaking god if they can do it.

lol sadly i'm christian so that just woulden't be right... well he was getting annoying... i don't think god would mind if i got rid of an annoying old man like that one time.

hey thats my catch phrase

I'd have yelled "what in Satan's glorious name?" and slammed the door in his face.