What I got of it was:
People follow religion like animals, where there is only a false belief within that religion. They may hold power and right upon living, where they can recruit, convert, tower over others. This man was a priest of sorts, spreading the good word and such.
However, these animals fall from their pedestal when they realize that they are vulnerable, that their faith in their god isn't as whollistic as their thought. This occurs when his child (I assume) dies before him, where he probably thought that he shouldn't have suffered this fate due to his belief in God.
So he has abandoned his religion, never really showing true faith in it in the first place.
I also think he goes "up" because he has realized his true weakness in his own religion and his faith in it. Instead of gritting his teeth and pretending that it is how He wants it, the man sees how he is an animal placed under the whims of another being, a higher being. This causes an overall reflection of how he treated others as his herd, making him think the he himself is a god among men.
Lol. Other than the subtext, I enjoyed the sharp contrasts and choice of colour. The reds give an uncomfortable look, but it doesn't distract from the movie. Great job!