Even if you aren't a believer, there are incredible stories in the 'good book' that I guarantee you will keep you glued to the page. The Bible is no less a part of our cultural heritage than Shakespeare is - and by the way, Shakespeare's plays are absolutely loaded with Biblical references.
If America is an idea, which it is - we're not a nation of ethnic groups that say we're Americans because we have American blood; we have the blood of every nation in our veins - and there's something really beautiful about that, but it means that we are an idea and that we all have to buy into this idea.