Thanks for the responses.
Yes, I think sometimes the writer of a Gospel episode was quite simply wishing to comfort or inspire awe. That is a message in itself. If that can be accomplished by writing a story of how this character could calm the sea or heal a leper, that was a sufficient motive.
I think of the "Left Behind " series of books that were so popular. few years ago. I imagine the author had religious motivations and used storytelling to communicate them. Was he trying to deceive? No just communicating his religious beliefs.
In the case of the earliest forms of Christianity, as I understand it, they had an invisible God having sacrificed an invisible Son on an invisible plane of heaven (on a tree, yes trees were thought to be in heaven as earth was thought of as a reflection of heaven) by invisible forces of darkness. How do you make this potentially abstruse, abstract, distant drama meaningful?
By drawing extensively on OT (otherwise sacred stories) and building out a new story with the main "spiritual" elements incorporated.
Now it may not have happened in exactly that way, but, in some fashion, the fondness for midrashic adaptation of existing stories is evident here. When the story making officially stopped by the new Catholicizing movement and only approved stories were Canonized, Christianity became poorer. The faith became a church, the Church was now the faith.