'... the Bible in the first instant is about ones morals and beliefs...'
Err............nope, it isn't. That might be a widely held belief, but it's wrong. The focal point of the Bible is messiah Jesus, the Son of God. Says who? No less a person than Jesus himself:
25 And he said to them, “O foolish ones, and slow of heart to believe all that the prophets have spoken!26 Was it not necessary that the Christ should suffer these things and enter into his glory?”27 And beginning with Moses and all the Prophets, he interpreted to them in all the Scriptures the things concerning himself.
And his disciples said the same:
45 Philip found Nathanael and said to him, “We have found him of whom Moses in the Law and also the prophets wrote, Jesus of Nazareth, the son of Joseph.”
Concerning this salvation, the prophets who prophesied about the grace that was to be yours searched and inquired carefully,11 inquiring what person or time the Spirit of Christ in them was indicating when he predicted the sufferings of Christ and the subsequent glories.12 It was revealed to them that they were serving not themselves but you, in the things that have now been announced to you through those who preached the good news to you by the Holy Spirit sent from heaven, things into which angels long to look.
1 Peter 1
And that's just a small fraction of the evidence that attests to the same fact. So if you want to know what is the central theme of the Bible, is it possible that the Bible's own testimony on the subject might be a bit more reliable than our own misconceptions or other widely held beliefs?
In fact, speaking personally, it is precisely this miraculous feature of the Scriptures that provide possibly the greatest proof of their inspired/divine origin. No work of man could concoct such a narrative.