Outside of the Bible, itself, this may well be the single most important book I have ever read.  I cannot urge people to read this book strongly enough.  In fact, for any believer, or anyone who seeks to understand the Scriptures on their own terms, this book should be mandatory reading.  I consider it to be that important.  If you have not read it, buy a copy today, then make time to read it.  It will be one of the most enlightening experiences you will ever have.