This question must be one of the most important questions for a preacher. It will affect how and why he speaks in his sermons. It is also a live question in the minds of his hearers and they deserve a good answer.
I am currently reading “Scripture and the Authority of God” by N T Wright which gives a good but not completely convincing answer.
A Google search threw up a Gem of an article by Don Carson which reviews this and other recent books. I am grateful for people like Carson who read stuff and then summarise it and comment on it so well. It means I don’t have to 😉
and you might well like to check out the whole Site: