Keller is a wonderful pastor and theologian and any of his stuff is worth your read. Check out the following review of his new book, Walking with God Through Pain and Suffering, and then consider reading it. I know very few folks who have walked away from the faith who have not cited suffering and the existence of evil as a major cause.
From Christianity Today online.
Walking with God through Pain and Suffering (Dutton) adopts a surprisingly broad perspective. The book is at turns apologetic, theological, and pastoral. As an apologist, Keller, founding pastor of Redeemer Presbyterian Church in New York City, explains how other religions and philosophies address and answer the problem of evil and suffering. After exploring these options (Stoicism, Buddhism, and several others), he demonstrates convincingly that the Christian answer is both more intellectually satisfying and personally helpful. But, he adds, it must be the genuine Christian answer rather than some insipid and superficial expression of Christianity.
It is only in the past 200 years, Keller argues, that Westerners have used evil and suffering as an argument against the existence (or goodness) of God. He is especially critical of the modern and secular view of suffering, which places all confidence in human reason and assumes that God, if he exists at all, exists solely to make us happy. This view helps explain why so many people avoid suffering at all costs, do their best to manage and minimize it once it interrupts their lives, and often yield to utter hopelessness when it persists. In the end, a secular view leaves us empty and alone, stripped of answers, devoid of all comfort and confidence.
The Christian answer to suffering, on the other hand, is more consistent, complete, and humane than any of the alternatives. It is attentive to human emotions. It views God as both sovereign and suffering. It alone satisfies the human longing for meaning and significance. And it is by far the most hopeful. Keller sums up the Christian perspective with the metaphor of a furnace. The flames of suffering consume our sinful inclinations, and yes, this is painful. But this purification process makes us holy, provided we turn to the God who reveals himself as both transcendent and present, Victor and Victim, Lord and Servant.