Molly said:
Aramaic's still alive...

I honestly haven't seen the Passion, so I wasn't really sure what language it was they spoke in it. I knew it was either an endangered or extinct language. In any case, Wikipedia has just revealed that native Aramaic speakers found the use of Aramaic in the passion to be "stunted and unfamiliar" meaning it's usage as an alien rather than terrestrial language is slightly more justified.

Any similarities can simply be explained away as being merely similar, like the way Ewokese is sometimes similar to Tagalog and Swedish.