I hold a particular belief that I… don’t really talk about because I also have a deep loathing for all forms of proselytising (the concept of “software evangelism” makes me uncomfortable, and especially so when that is a titled position at a company someone can be hired for. Ick.).
It is that non-consensually invoking deities is, at best, rude.
Invoking one’s own deity, or a spiritual presence one worships or follows, is an invitation for that being to take notice of you, and of your surroundings. Doing so in the presence and to the face of someone who is not expecting that kind of attention is at best rude, if that person also happens to follow your same set of beliefs. If that person is following a different one it’s even more distasteful, at best.
Invoking someone else’s deity or spiritual etc when you do not subscribe to them yourself is also rude and potentially an affront.
Asking for a blessing from your patron spirits onto someone who has not consented to being brought to the attention of said spirit could well be considered an indirect attack. Asking for a blessing from deities you don’t even subscribe to is just plain weird to do directly, though soliciting attention from ones via people who are is acceptable (so long as they consent to).
Yes, this all applies even though I am an atheist. One could think that as an atheist I wouldn’t care about “imaginary beings taking imaginary attention to me,” but I suppose I am very slightly on the agnostic side for that: in the optic that “we can’t be sure,” I would say it would be prudent to not randomly invoke gods and goddesses for no fucking reason.
Anyway, that is to say, I understand it is a very ingrained tic in the English language to do so all the bloody time, but if you can at all refrain, please do not say “oh my ---” at me. Especially if you don’t actually have religious beliefs, that just feels super weird to me. Why.
Less controversial perhaps, saying “--- bless you” is also off. Saying just “bless you” is… marginally okay, only in that it can probably be “I bless you” or something, like you’re bestowing the blessing, you’re not invoking some extra-universal entity to pull on the fabric of spacetime to arrange things my way. If you want to be all proper about it you could ask for permission; it’s not something very done in these times, but it could stand to make a comeback.
As an aside, I’m somewhat confused at the habit to censor the name of your own deity while keeping with calling them all the time. Like maybe if you have a religious dictate not to openly refer to your deity and you’re interpreting that as an injunction to very lightly censor the word “god” while still keeping the same frequency of saying “omg, OMG OMGGGG, OH MY ███”… that feels rather counter-productive? Excising the word from your language seems like a much better way to follow such a dictate. But what do I know, I’m (in this) only an atheist.