The proof for believing this information is on an individual basis, person-by-person, to be accepted or rejected. If the person believes the Bible to be true, then they act accordingly as well as vice versa. It can't be proven absolutely true for everyone.
I am in between these two extremes of 'all or none' regarding the Bible. I have no problem accepting the parts that are compatible with the God of the universe as defined by me. That definition IS as absolute as Ron Paul's voting record (power, love, forgiveness, mercy, generosity, honesty, compassion, etc.). However, I also have no problem rejecting the parts that are inconsistent with that definition (hate, revenge, murder, genocide, debauchery, etc.).
Faith comes from believing that which cannot be proven, so there is a reason for having equivocal Biblical evidence, IMO. We have been given the capability by The Almighty to sift through all of this information and figure out what are the absolutes worthy of being called the "Word of God" and what are not.