Have you (or someone you know) ever had to face a new language in your religion of choice, such as having to learn a whole new language in order to participate?
No, learning the language(s) was my choice.
When I was Eastern Orthodox Christian, I picked up some Russian and Greek. But the churches I attended are in the US and use English, with only a few smatterings of Russian and/or Greek.
I'm not fluent, but I'm often shocked at how much I've actually picked up, especially in the Sansrit department.
My Sanskrit sucks, but it's getting better. I'm beginning to get the pronunciation subtleties down better. I just can't read it or speak it. However, I understand how Sanskrit works, and how it inflects; just like Latin, Greek, Russian and other highly inflected languages.
For example, the "ya" ending in Shivaya, Narayanaya, Krishnaya is the dative meaning "to Shiva", to "Narayana", "to Krishna". The feminine adds an /i/... Durgayai, Kalikayai, Saraswatiyai. I'd like to learn it fully, especially to read devanagari.
J. Robert Oppenheimer, of the Mahattan Project and Trinity blast fame, taught himself Sanskrit and read the Bhagavad Gita in the original Sanskrit. After the Trinity test he quoted the Bhagavad Gita 11.32
"...Time I am, the great destroyer of the worlds, and I have come here to destroy all people. ..." but he translated it as
"Now I am become Death, the destroyer of worlds".
Now I'm showing off.