The Problem of Pain, How Human Suffering Raises Almost Intolerable Intellectual Problems, by C. S. Lewis (published 1940)
As I've mentioned elsewhere, many years ago I was a self-professed atheist. Yet I considered myself open to opposing views. It was in this spirit of open mindedness I accepted a short work a friend and mentor loaned me called Mere Christianity, by C.S. Lewis. Directed to skeptics who seek intellectual reasons for faith, it forced me to question my disbelief. It would be another decade before I squashed my pride, confronted its truth, and converted. (Guess I wasn't so open minded after all.) But that's another story that deals more with the heart than with the head.
I'm convinced that Lewis' conversion from atheism to Christianity contributed to his insight and argumentative powers. Such converts, whether it's the great economist Thomas Sowell (having first been a Marxist before embracing capitalism), tend to speak and write with more authority than those who carry the same political or religious views from cradle to coffin.
I'm not suggesting converts ipso facto make for persuasive writers. Nor does doing an ideological about-face necessarily mean one is more objective or sincere than the next guy or gal. But a lot can be said for having not only examined and lived opposing doctrines but articulating what precisely changed one's mind.
Lewis begins The Problem of Pain with the strongest case for atheism I've ever read. In fact, ironically, I haven’t come across a more compelling argument than the one this former atheist poses. Lewis then goes on to show how such an argument is not only too simple but self contradictory.
The Problem of Pain isn't a self-help or how-to-grieve type work. Nor is it for everyone. Those who lack faith in God or a fundamental knowledge of theology will be as lost as the student who skips basic math and jumps straight into physics. This is for people of faith who want rational answers to perhaps the most challenging question facing believers – why we suffer.