The symbol of note is not "The Star of David", but instead Ouroboros, the eternal snake... symbolized by a snake eating his own tail.
I believe he chose the symbol Ouroboros to represent the "immortality through change" of the code. In one story... Ouroboros was an immortal snake who constantly shed his skin, and took on many forms.
Similarly, this code constantly changes form, yet is immortal. While it changes form, it manages to keep its identity.
The Star of David is incidental. As far as I know... it was added to the Ouroboros symbol in the anime/manga Full Metal Alchemist, but that rendition is perhaps the most famous artistic rendition of Ouroboros in recent culture.
Ouroboros had some connotations in the classical psudo-science of Alchemy as well. So perhaps there is an earlier version of Ouroboros + Star of David.
> The Star of David is incidental. As far as I know... it was added to the Ouroboros symbol in the anime/manga Full Metal Alchemist, but that rendition is perhaps the most famous artistic rendition of Ouroboros in recent culture.
The "Star of David", like many Jewish symbols, has long been associated with alchemy and magic arts (and other less savoury enterprises) in classic European cultures. See for example [1] from a basic google search. This is likely why it was used in the anime, probably just to avoid the usual boring pentagram.
Which means it gets shown in anime for pure Rule of Cool reasons, and then Japanese people have not the slightest idea that it's actually the flag-symbol of Jews.
It's not like I would know the standard symbol for Shintoism unless I googled it.
Actually, the Ouroboros Tattoo on the villians Lust / Gluttony / Greed / etc. etc. from Full Metal Alchemist, of whom were created using the human transmutation circle (getting into the details of which would be spoilers...).
