The Bible is God’s Word because it says so. You might be inclined to object that this is a circular argument. And you would be right if you did! Ultimate authority must be self-authenticating (See the Frame link at the end of this post). Otherwise, the authority to which one appealed when verifying itself would be the authority. The Bible, then, is God’s Word because it tells us its God’s word. This is a circular argument, but it is not “narrowly circular” but broadly so.