It sounds like the main character was American. As such, he may not have spoken other languages.
Sorry, but that doesn't hold up. Sam Beckett holds six doctorates, one of them is in linguistics. In one of the first episodes, he reads hieroglyphics, even.
(as the sequel show already has another one)
?!? I saw no other leaper in that one episode.
Perhaps, the main character being an American is sent to help out American problems, but if they were from another location they would help out with that locations problems?
I am not a fan of addressing major issues in a show with stuff that isn't even hinted at in the text. We can make up non-canon excuses for virtually anything.
The point is that linking religion to American only would be a source of criticism from a goodly chunk of the audience these days. They'd have to explicitly address it on screen to not have folks complaining to them.