The Bible doesn’t SAVE you (as some fundamentalists border on preaching), but it isn’t just a book full of information either. Being the core of the special revelation to mankind, it’s actually part of the gospel itself. N.T. Wright explains here.
…for Jesus’s death to have the effect it was intended to have, it must be communicated to the world through the “word” of the gospel. (As we saw [earlier], God’s “word,” for the early Christians, was the powerful proclamation of Jesus’s lordship.) And the Bible, in setting out the roots of the Christian story in the Old Testament and its full flowering in the New, was seen from very early on as encapsulating that powerful word – the word which communicated, and so put into effect, what God accomplished in Jesus. The Bible, in fact, is not simply an authoritative description of a saving plan, as though it were just an aerial photograph of a particular piece of landscape. It is part of the saving plan itself.
-N.T. Wright, Simply Christian, p.185