I'm doubtful if religion has a place here: 'thy' is not consistently used, could just be old language use, and the wife says "I'll bloody not", not too decorous for any strict religious types, plus they're all in a tavern. It sounds to me more like a story set post world war I, or possibly an earlier war. Conscientious objectors were relatively common in Canada, and my greatgrandfather, alive at the time, did unselfconsciously use 'thy', in Cape Breton, and not due to religious usage, and horse driven conveyances were common.

But yes, a case of shock all around at bloodshed occurring, I think.

You could speculate the wife responded with a slap as an outraged defense of her reputation and honour.