Never thought about what it meant exactly when I was young. Looking back, it just seems to be a metaphor for the belief that all things will be revealed and made plain in a final accounting and sorting-out. I'd rather not think about how old I was when I first realized that it was (or should be) wash cloth, rather than warsh rag. Southern parentage, you see. And I don't mean that as anything but a statement of fact. It's one thing when we call each other "hillbilly," but quite another when an outsider says it. Kinda like the "n word."