Proverbs 30:6
Do not add to his words, lest he rebuke you, and you be found a liar.
Talking about Revelations specifically, but could possibly be applied to the entire Bible:
For I testify to everyone who hears the words of the prophecy of this book: If anyone adds to these things, God will add to him the plagues that are written in this book; and if anyone takes away from the words of the book of this prophecy, God shall take away his part in the Book of Life, from the holy city, and from the things that are written in this book.
Revelations 22:18,19
I just though I might throw those out there; interpret them as you will.
The Bible is silent on the fate of those who die without having had the opportunity to accept the gospel of Jesus Christ. It is impossible to contradict something that isn't there in the first place.
No it's not.
So they said, Believe on the Lord Jesus Christ, and you will be saved, you and your household.
Acts 16:20
He who believes and is baptized will be saved, but he who does not believe will be condemned.
Mark 16:16
That is just a dent in what one must do in order to be saved. The Bible makes it rather clear that if these things are not done, you will be condemned. If you've never heard of Jesus, tough luck. I know that sounds horrible, but that's the way it is.
However, in our day and age, it's almost impossible to have never heard of Jesus.