Based on what scientific knowledge?
"Based on what scientific knowledge?"
The usual culprits, archeology, carbon-dating, tribal migration. From a christian point of view I really don't think God cares except that you believe what his Son put out. And I'm completely comfortable with that. Even Jesus was irritated with the jewish leaders at the time for having him clarify supposedly contradiction of historical social guidelines.
Most reports of God's show of power in the bible has been cataclysim of natural elements, a huge expense of energy that even He had to rest to have a gander at what He did. Could have taken 4 billion years to do the 'six days'. Who knows? Nobody was there, and this argument will be argued until the second coming. The first law of thermodynamics plays nicely into the whole discussion. God is the purity of energy and the purveyor of all unversal elements. He got lonely and made man and gave us free will and a lot of us screw it up. He decided to send an earthly represenation of himself to appeal directly. And we killed his physical form. Great show of appreciation. Oh well, some get, some won't.