Religion, in the most general sense of the word, is a collection of and a base framework of thoughts, ideas, and even words needed to understand the supranatural.
It is a tool that functions almost like a spyglass, telescope, or kaleidoscope(or stained glass window) that allow us humans of the physical world know and perhaps understand something that is beyond our physical senses. Just like a real telescope/spyglass/kaleidoscope it will both and simultaneously reveal and distort in some way. This creates both truth and fiction simultaneously.
>"There is some fiction in your truth, and some truth in your fiction."
Personally I don't believe there is any religion that can be 100% true due to the limits of words, language and our current physical selves, but also there is no religion (no religion believed by at least one single person) that is 100% false for no religion can be believe at all unless it possesses a minimum a single grain of truth to it.