William W. Klein, Become What You Are; Spiritual Formation According to the Sermon on the Mount (Tyrone, Georgia: Authentic Publishing, 2006), 238pp.

           I read this book while ending a business relationship that had gone very bad and very expensive. I still have a few notes that I took on the radically subversive words of Jesus from the Sermon on the Mount—to deride a person as a fool is as bad as murder; settle matters quickly with those from whom you are estranged; be merciful; don't swear falsely or bear false witness; don't resist an evildoer; and give to those who ask of you. Or maybe I should go to court, get even, get my due, and make him pay? No wonder that at the very end of Jesus's provocative preaching, "The crowds were astounded at his teaching, for he taught them as one having authority, and not as their scribes" (Matthew 7:28–29).

           New Testament scholar William Klein (Denver Seminary) has written a simple exposition of the Sermon on the Mount that sparkles as a model of clarity, accessibility, and, most important of all, practical application. His goal for his readers does not stop with theological information. He aims for genuine transformation, or spiritual formation, from the inside out, what he calls "a change at the inner center of our being." The Sermon on the Mount, he writes, is "the quintessential explanation of who God's people are and what he desires them to become."

           After an introductory chapter and a chapter on the setting of the text, Klein spends eight chapters expounding and applying the text. Each of these chapters begins with a brief analysis of the text, often no more than a page or two, then ends with applications, questions for real life practice, and personal reflection. Footnotes and bibliographical materials are modest but adequate for his purposes. I especially enjoyed his provocative questions. For example, how would my financial giving change if God alone knew what I gave? Klein also enhances his message by sharing some of his own successes and failures in spiritual formation (praying, fasting, anxiety, etc.). Like any good book, Klein leaves you wanting to dig deeper. Just when might a Christian consider divorce? Why do we not invoke the death penalty for adultery, as in the Old Testament? Exactly what is a pure heart? How does one judge wisely but avoid judgmentalism? I have always appreciated fine scholars like Klein who, in addition to their technical scholarship, write for the ordinary faithful, all of whom will benefit by considering his guide through these most famous words of Jesus.