Generic religion and spirituality can survive a mindless conservatism or a mindless liberalism, but Christianity cannot. It thrives in an atmosphere of questioning, engaging, wrestling, listening, and reading. If we are only looking for whatever "works"-for the moment, at least for for what is entertaining, fun, or affirming, we will always be spiritual infants, if Christians at all. Michael Horton
Religion and spirituality are chiefly about how to attain power: power over oneself, one's destiny, others, and even God. The gospel, by contrast, is God's power for salvation (Rom 1:19). It is God's means of saving us, not a "to-do" list for saving ourselves. Michael Horton
Sociologists have pointed out that when Europeans go "secular," they become atheists, but Americans secularize their faith by blending an enthusiastic personal faith with the pragmatism and narcissism of our popular culture. It may be a deeply personal, exciting, and emotional spirituality, but it need not bear any direct connection with historic Christianity. Michael Horton
A few quotes from the Viewpoint discussion between the Washington Post and Michael Horton on his book "Christless Christianity". Read the rest of the discussion here.
JD's add: Good article by the author with same name here.