just because he was carrying around a braille bible doesn't mean he has to be blind
you don't have to be blind to read braille and you certainly don't have to be blind to memorize the bible
sure, the character may be blind, but the actor was clearly looking specifically at things making noise / people talking meaning something somewhere got fucked up in translation which is part of what makes this a mediocre twist and ultimately mediocre movie.
He's blind. There are several clues in the movie that points towards this, and several clues that show he has heightened senses such as hearing, and smell which blind people develop because when you lose one sense the brain focuses more on the other senses. Don't forget he also says he walks by faith not by sight. Below are some clues.
1. When he walks into an abandoned house he's feeling around on the shelves to find items making all the plates move, some one who could see would have no reason in doing this.
2. When he finds the skeleton in the car he feels on it's feet to see if it has shoes, if you could see you wouldn't have to touch it.
3. When the mouse comes he tells the mouse if he wants food he has to come get it, pointing towards that he isn't able to see him.
4. When his IPOD is dead he keeps pressing all the buttons because he can't see the battery low indicator on the screen.
5. He fights the ambushers in the dark to give them a disadvantage because he doesn't need to see and uses his heightened sense of hearing, if he could see wouldn't you stay in the sun light where it's easier to see?
6. When he's walking with Solara he tells her to be quiet so he can hear the birds above and is able to shoot one to eat.
7. When he's walking to the house with the old couple he kicks the first step to check if there are stairs there.
8. When the old couple tells him there's a no trespassing sign he says he didn't see it, even though he clearly walks right by it.
9. He clearly has a heightened sense of hearing because he never shoots unless some one shoots first because he won't know where they are, and then in the town when the last guy is left pointing a gun at him he doesn't do anything because he doesn't know where he his unless he shoots first.
10. It's also clear that he has a heightened sense of smell because he can smell the ladies shampoo, he says he can smell the ambushers from miles away, he can smell the salt from the ocean which Solara doesn't smell.
11. He has the old guy write everything he says, wouldn't it be easier to write everything yourself if you could see?
12. He also always turns his face to the sunlight so he can feel the heat from the sun so he knows it's day.
13. Whenever he gets water he smells and tastes it first, any one who could see clearly knows what water looks like.
14. In the pawn shop when he turns the lighter on he moves his hand over it so he can feel the heat from the flame so he knows it's working.
God also leads him to find a bible written in braille, if he could see why wouldn't god lead him to a bible with words?