Wrong for what? You need to state a purpose. If your purpose is to maximize satisfaction in a community, then yes, it is wrong.Now here is the question you won't be able to answer: Was it wrong for that person in that society to rape.
Because rape doesn't serve that purpose, and shouldn't be tolerated.If so why?
You seem to consider these posers. This stuff isn't as difficult for me as it seems to be for you. But I suspect that is because of what is likely our different upbringings, our differing philosophies, and our different life paths since then. Rational ethics is really not that hard, but you have to learn how to do it. I don't see where a theist would have the opportunity to learn, given your metaphysics.