Several ways for me and many of them can be verified in secular sources. -The historical accuracy of the history books of the Bible, specifically acts. -historical events written about in the Bible accurately centuries before they actually happened (four major world empires, alexander the great). -100's of prephecies concerning Christ that were fulfilled in his birth, death, and resurrection -the Bible contains 66 books written by approximately 40 different authors over a span of about 2,000 years. There are no contradictions anywhere and all of the books have the same central theme, God's plan of salvation for man.