A few searches of these books using Amazon's "Search Inside" feature provides some objective evidence that these arguments are not entirely unfounded.

For example, Joel Olsteen's book, Your Best Life Now, mentions "Jesus" on only 20 of the book's 324 pages.

Even worse, Olsteen's Book "Become A Better You" only mentions "Jesus" on 24 of the book's 404 pages.

Jack Canfeild's Chicken Soup For The Christian Soul mentions "Jesus" on 46 of the book's 424 pages.

In contrast, the NIV Shirt Pocket New Testament mentions "Jesus" on 296 of the book's 422 pages.

And even Christopher Hitchens' book, "The Portable Atheist: Essential Readings For The Nonbeliever," mentions "Jesus" on 66 of the book's 530 pages.

Of course, just as one should not judge a book by its cover, one should not judge a book solely by the number of times it uses a particular word or phrase. And other popular Christian books fare somewhat better. For example, Rick Warren's The Purpose Driven Life mentions "Jesus" on 24 of the book's 132 pages.

Moreover, the fact that a particular book has a broader focus does not necessarily mean that the book is itself "watering down" the gospel. After all, such books arguably bring Biblical and Christian principles to a wider audience, an audience with real problems and challenges that would otherwise never be exposed to such ideas.

And while these books may not focus exclusively on the Gospel, they do at least make the world a little better, in accordance with the Biblical observation that Christians are "the salt of the earth."

They might also provide a bridge to unbelievers seeking something beyond mere self-improvement. If the book does not change the Gospel, the fact that it does not emphasize the Gospel, does not, in and of itself, minimize the importance of the Gospel message.

In addition, such books may have an important role in today's culture, providing a Biblical perspective on the latest trends and interests of readers.

Observers are often citing such "new" trends. For example, Americans are increasingly interested in self-improvement, and get much of their information on this topic from books and television programs, such as Oprah and Dr. Phil.

Americans are also increasingly interested in spirituality. For example, it was widely reported last week on Christian News websites that the Southern Baptist Theological Seminary would be the first Protestant School in the United States to offer a PhD in "Spirituality." The school hopes to provide a "true" understanding of Christian spirituality. Perhaps Christian books can similarly address these and other trends, providing a "true" Christian understanding and perspective on subjects of interest to modern culture.

But does that lessen or diminish the gospel, creating a "gospel lite" which is a pale comparison to a matter and a message that some take quite seriously?

Does it turn the hidden treasure of the Kingdom of Heaven into a cheap commodity that simply offers a few ideas for self-improvement?

Ultimately, most believers' time might be better spent focusing on the positive benefits associated with popular "cross over" books, rather than fretting about the image or brand of the Gospel, which today's popular culture trashes on a regular basis.

At a minimum, such books likely reach readers that would never enter the door of a church, in accordance with the well known missions directive that Christians are to "go ye into all the world..." (never mind the "preach the gospel" part).