The movie seems to be more about the sentiments of the bible and god, than christianity. There was even a point where Eli and Solara slept in the stack, and he explained why he had the book, he said there were wars over it. The bad guy (forgot his name) said its used to corral the conscious of the poor and suffering. So I didnt see the movie as a positive reinforcement of christianity at all.
It also shows that the stories in the holy books are simply constantly recycled and most likely hundreds of thousands of years old but the earth constantly has its reset button pushed. Water was the most prized commodity in the movie . Eli was the sole holder of the passages in the bible and he told it to that guy on alcatraz who then printed the bible "alcatraz edition".
The main antagonist was named "carnegie" thought that pretty clever,
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