"Skeptics believe that any exclusive claims to a superior knowledge of spiritual reality cannot be true. But this objection is itself a religious belief. It assumes God is unknowable, or that God is loving but not wrathful, or that God is an impersonal force rather than a person who speaks in Scripture. All of these are unprovable faith assumptions. In addition, their proponents believe they have a superior way to view things. They believe the world would be a better place if everyone dropped the traditional religions' views of God and truth and adopted theirs. Therefore, their view is also an "exclusive" claim about the nature of spiritual reality. If all such views are to be discouraged, this one should be as well. If it is not narrow to hold this view, then there is nothing inherently narrow about holding to traditional religious beliefs."
- Tim Keller, The Reason For God, pg. 12
I've just finished the intro and the first chapter of this book. The introduction may possibly be the most attention grabbing introduction that I have ever read. This book is Keller's effort at engaging in Paul's task of reasoning in the Areopagus. A friend recently recommended this book as the most important book he read last year. After reading the introduction and the first chapter I can see why.
Here is a great example (mp3) of Keller also doing this in his preaching.