I'll bite. For many reasons but the one that I think will interest you most is archeological and historical. Every year more and more historical information in the Bible is proven to be accurate when they were previously declared mythical by the scientific community. The city of Ur (from which Moses came) it was said never existed until they found references to it in unearthed historical documents. The story of Jericho was said to be a myth until the remnants of the walls were unearthed in positions consistent with that of a great earthquaked. These are relatively (in our lifetimes) recent discoveries. Over the centuries, more and more biblical history is proven true and accurate. And then you have the prophets which predicted historical events that happend hundreds of years after they predicted them (fall of Jerusalem to the Babylonians, etc.).
The monthly publication "Biblical Archeology" has enormouse amounts of information on this type of thing if you are interested.
????? Abram/Abraham ????