The Reason Religion Persists: Fear of Death

Jesus death

Paul Waldman hits the nail on the head in a recent article in The American Prospect when he provides this answer to the question of why religion has persisted even as science and reason have made it less necessary:
Why? Death, of course. Which helps explain why religion has such staying power.
Drawing on data from a recent survey of 30 countries conducted by researchers at the University of Chicago, Waldman notes that religious belief is declining across much of the world at a very slow rate. You have undoubtedly heard many atheists talk about the cohort effect, which shows that younger generations are less religious than older generations. This gives many of us hope because it suggests that we are gradually outgrowing religion. However, Waldman also points out that aging appears to affect the data such that individuals tend to become somewhat more religious as they age.
As in so many other areas, we are more likely to believe that the thing we would like to be true is in fact true. As you age you see more and more of your family and friends die, and the thought that they are living in paradise and you'll see them again one day is enormously comforting… Even more powerful is the thought of your own mortality, which becomes harder and harder to ignore with each passing year.
So for those asking how people can continue to cling to religious belief in our modern age, at least part of the answer would appear to be the reality of death and religion's promise of immortality.