There are people that has read and re-read the bible infact the word of of God has so sticked to there mind, there brain, and there heart no doubt , they now see it as nothing much or nothing difficult because they are familiar with the bible.
Consistency in reading and studying the word of God is needed for one to understand, you can't just understand the bible just because you want to or because you are intelligent no it doesn't work that way.
It takes the grace and intervention of God and your deligency and eagerness and the holy spirit. For one to understand the bible.