NT Wright from a post The Problem with Biblical Authority:
Why would we even want to mention biblical authority? Why not say, “We live under Jesus’s authority,” and leave it at that? Wouldn’t that be the biblical thing to do? Well, yes, but as centuries of history demonstrate, the Bible is the God-given means through which we know who Jesus is. Take the Bible away, diminish it or water it down, and you are free to invent a Jesus just a little bit different from the Jesus who is hidden in the Old Testament and revealed in the New. We live under scripture because that is the way we live under the authority of God that has been vested in Jesus the Messiah, the Lord.
On a related note, here is a story with a chart about what people say about the Bible.