Thomas Merton is one of the most important spiritual voices of the last century. He has never been more relevant as new generations look to him for guidance in addressing some of life's biggest questions: how can we find God, how should we engage with other faiths, and how can we oppose violence and injustice? Looking carefully, one can find, tucked away in Merton's prodigious writings, his response to another timeless question: Why do we suffer? Why does an all-powerful and all loving God permit evil and suffering? By carefully examining all of Merton's work, we find that he repeatedly confronted this question throughout most of his adult life. Intriguingly, Merton's approach to this question changed dramatically a few years before he died in 1968. An examination of all aspects of his life yields evidence that Merton's immersion in Zen during this time contributed most to that change.