In my experience even your basic moderate, grassroots, non-evangelising xtian seems unable to resist the occasional preachy urge, like a kind of Jesus Tourette's. At least when faced with such I had to option to walk away whenever I liked. Were I to be trapped with them in the proposed scenario I'd probably spend the day banging my forehead against the wall, or sitting on the floor in the furthest corner possible from them, clutching my knees to my chest, staring into space and moaning to myself. All involuntary actions, to be sure, but satisfyingly worthwhile relative to actually having to interact with them. Plus there's the added bonus of keeping them well away from me - particularly if I can incorporate drooling in some way (I do a good drool when I have to; but that's another story for another time).
At the age of five, Skagra decided emphatically that God did not exist. This revelation tends to make most people in the universe who have it react in one of two ways - with relief or with despair. Only Skagra responded to it by thinking, 'Wait a second. That means there's a situation vacant.'