Why Do Many Jews Write ‘G-d’ Like This
For some (but not all) Jews, it’s actually a sign of respect NOT to write G-d’s name in full. The concern is that the word may be written on something that will later be thrown away or otherwise destroyed. For example, you might print out a copy of an article that mentions G-d, but later toss it in the trash along with old coffee grounds. Not exactly a place redolent of majesty.
Judaism does not prohibit writing the Name of G-d per se; it prohibits only erasing or defacing a Name of G-d. However, observant Jews avoid writing any Name of G-d casually because of the risk that the written Name might later be defaced, obliterated or destroyed accidentally or by one who does not know better.
The commandment not to erase or deface the name of G-d comes from Deut. 12:3. In that passage, the people are commanded that when they take over the promised land, they should destroy all things related to the idolatrous religions of that region, and should utterly destroy the names of the local deities. Immediately afterwards, we are commanded not to do the same to our G-d. From this, the rabbis inferred that we are commanded not to destroy any holy thing, and not to erase or deface a Name of G-d.
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