In the final scenes of The Book of Eli (2010), Eli is dictating whole bible to Lombardi.
Why did The Book of Eli show the bible to have so many pages?
Typically, bibles are printed on extremely thin paper, much thinner than a normal book, with a very small typeset.
If you look at very old printed bibles, they tend to have fewer books in the Kings James Edition.
As such, with the number of books, small size of font, and thin pages, translating the bibles into hand written text would result in potentially thousands of pages. You can see in the image the relative size of the person writing's hand writing, he's fitting maybe 100 or so words a page.