I provided an answer to this question citing an example from Norse mythology, and it was deleted for being considered offensive:
It's not well-publicized, but we discourage citing religious texts as fictional works due to the risk of offending.
I've read a Meta question, considering exactly this kind of situation, and it seemed clear to me that such examples are valid. Besides, this particular question was asking for the earliest example of an often used story device, and we know Norse mythology by the accounts of many fiction books from Christian (non-believers) authors.
I did a quick google search to find if someone actually considers Norse Mythology a religion nowadays and it seems there is a German Neopaganism. Now, it's not in my interest to offend anyone but considering a census conducted in 2013 found 16,700 member, it seems odd that I should refrain from using Norse mythology as an example.