What’s Up With Writing “G!d”?
Sometimes — but not always — I will write “G!d” instead of “God.”
I am pretty sure I picked up that particular punctuation mark in the orbit of the Jewish Renewal movement. But it is an elaboration of a quite longstanding Orthodox practice of writing “G-d,” as a way of Anglicizing the custom of writing “ה׳” (abbrev. of “ha’Shem”/“the Name”).
There is a rabbinic mitzvah to not destroy any piece of paper with the name יהוה written on it (digital doesn’t count, apparently, don’t worry), derived from the VERY biblical mitzvah not to take G!d’s name in vain. That’s why we say “ha’Shem” even verbally, outside of prayer.
The rabbis have a way of being extremely over-cautious in their elaborations of Torah mitzvot, since in many cases we can’t be sure we’re keeping them closely in the modern context. So they went ahead and recommended “G-d” too, to be safe.
It seems silly kind of, but of course “God” isn’t even really a very Jewish word for ha’Shem at all, for many reasons, so “G-d” spread pretty far because of its usefulness as a way of saying, “Not the bearded man in the sky you’re thinking of.”
Whoever invented “G!d” was taking that deeper into the heart.