The rules are discussed here:
” “Closed” threads on the Religion Forum include devotionals, prayer threads and caucuses. The header of the thread should make it obvious that the thread is closed, i.e. like a church meeting behind closed doors. Such assemblies will not be disturbed. Any challenges or ridicule will be removed. Any thread can be designated a caucus - e.g. labeled as a “[Catholic Caucus]” or “[LDS Caucus]” - provided that neither the article nor any of the posts challenge or ridicule any other confession. These are “safe harbors” for those who are easily offended or are ill equipped to defend their own confession.”
http://www.freerepublic.com/focus/f-religion/1774184/posts
Safe harbors? There are plenty of places to find those. FR ought to be robust and candid, within limits of course. Those who are ill equipped to defend themselves in discussion have my sympathy.