It is not that God needs it, but from it we will get perfect copies after we are resurrected, and learn from them. And God will then explain everything in the Bible for us.
And God does not enjoy watching us argue over Bible interpretation, but tolerates it, because now is not the time for us to know everything about the religion. Now we should be humble and realize we can't understand everything in the Bible. God's plan goes by stages, some call them dispensations. There was a dispensation before Moses, with its laws. Then came the dispensation of Moses, with the Law of Moses, for Israelites, and just conscience for gentiles. Then the dispensation of the gospel, with the gospel laws. Then will come the millennium, with its laws. Then the eternity. God knows better than we do, why he does it by stages.