This has remained ambiguous at best in Star Trek where humans are concerned. Gene Roddenberry's first draft of TMP was called "The God Thing" and there have been many episodes in all of the shows that skirt around this issue. But at the same time, some characters have uttered "My God" or some permutation of this phrase. Obviously there are religions out there as the ENT episode 64 (3x12) "Chosen Realm" showed in no uncertain terms.Bjbeardse 23:31, July 19, 2011 (UTC)
While most Federation species have turned being agnostics or atheists, there are a few races like the Bajorans that remain religious. 126.96.36.199 23:49, July 19, 2011 (UTC)
It is interesting to note that all references to God were removed from the director's cut of Star Trek: The Motion Picture. DarthLucifer 22:06, August 22, 2011 (UTC)
Roddenberry considered himself a "secular humanist". He was said to have repudiated at least organized religion in the forms we have it in American or western societies. Although he rejected western religious dogma, Roddenberry was known to be partial to Japanese Shinto.
Piller, Berman and Taylor, obviously, were not as adverse to the idea, as a story vehicle. The "god" reference in earlier drafts of Star Trek: The Motion Picture was more to the idea of the "thing" being omnipotent, or, at least, so massively powerful as to challenge current human comprehension ProfessorTrek 23:05, August 22, 2011 (UTC)
I suppose there is some controversy as to Roddenberry and some of the other writers ideas toward religion but it's pretty clear that there are numerous societies in the Trek universe that do have some sort of religious belief. The Bajorans are a great example, despite the fact that science can explain some of the powers of the prophets and the existence of the wormwhole they still are very faithful. The Jem'Hadar and the Vorta believe the Founders are gods, now of course they have been genetically engineered to think so but if one defines "religion" as some concept or belief in the existence of some kind of supernatural "godlike" force then this is also an example. There's also numerous other Star Trek cultures that have a deep and very present set of traditions and rituals like the Klingons and Vulcans. Though their rituals don't appear to be distinctly religious in nature I do think that this is also worth noting.
Ritualism is, by definition, religious in nature, unless psychopathological considerations control ProfessorTrek 12:17, August 23, 2011 (UTC)