I myself tend to hang out with flippant atheists more than with devout Christians, but I think PM should be reasonably hospitable to technical contributions from both.

People will make mistakes. The whole idea of an exclamatory oath, or a joke, is that it crosses or plays with some boundary, and that leaves lots of room for error. Some people will use the boundaries of thier own associates, and forget others present, especially on-line. I think such mistakes deserve a polite reminder, as in

You probably didn't realize it, but that expression is deeply offensive to some, so you probably don't want to use it.

This response is best from someone who is not deeply offended, since such measured politeness is asking a lot from someone who was, in fact, injured (unintentionally).

It's true that some take a certain macho pride in casual blasphemies that offend those outside their group of compatriots, but courtesy requires giving the poster the benefit of the doubt; sometimes it's just a mistake, or ignorance. I think repeated offense and insistence on the right to offend, short of the "egregious" level, deserves at least one response along the lines of "please don't be a jerk", as well as downvotes. (And nothing more. Atheists are not immune to the attractions of righteous martyrdom.)

That leaves the naive, those who think the offended are "just being silly" and it shouldn't be that hard to "broaden one's view". They should be directed to discussion of indentation style, or those about which programming language is better.