This blog series on Reflections is intended to encourage Christians to read more vigorously by providing a beginner’s guide to some of the Christian classics in such fields as theology, philosophy, and apologetics. Hopefully a very brief introduction to these important Christian texts will motivate today’s believers, as St. Augustine was called to in his dramatic conversion to Christianity, to “take up and read” (Latin: Tolle lege) these classic books.


This week’s book Cur Deus Homo (Latin for Why the God-Man?) by St. Anselm is considered one of the most important works of philosophical theology in Christian church history. Anselm’s book seeks to provide a rational explanation for one of Christianity’s most important and mysterious truth-claims.

Why Is This Author Notable?

St. Anselm of Canterbury (1033–1109) is honored as a doctor of the Catholic Church and has been recognized as the greatest Christian thinker between St. Augustine and St. Thomas Aquinas. He is well-known for his understanding of the relationship between faith and reason and for formulating one of the most distinctive arguments ever for the existence of God—the ontological argument. For more about him and his accomplishments, see my article, “Christian Thinkers 101: A Crash Course on St. Anselm.”

What Is This Book About?

As a work of philosophical theology, St. Anselm attempts to provide an explanation for possibly the greatest Christian mystery of all, for as the Latin title asks: “Why the God-Man?” Thus, Anselm lays out a broad theological theory for why it was necessary for God to become man in Jesus Christ and for the Son of God to suffer. This is then a rational defense of the necessity of the incarnation in light of the atonement.

Divided into 22 chapters, Cur Deus Homo consists of a dialogue between Anselm and Boso, a fellow monk and colleague who takes the role of the questioner and infidel (unbeliever). Through this dynamic philosophical-theological exchange Anselm sketches out the following explanation and defense of Christ’s identity and work.

While humankind was specifically created to love and serve their Creator, man’s sin has injured God’s honor. Thus, some form of satisfaction to restore God’s honor is required. However, because God is an infinite being, the dishonor reflects an infinite debt. Thus, the problem is that while the payment must be accomplished by man who transgressed against God, it is clearly beyond the capacity of mere human beings to repay.

Anselm’s theological conclusion is that only the God-Man (Jesus Christ as a single person with both a divine and human nature) can make the necessary payment to restore God’s honor and restore humankind’s relationship with God. Because Jesus Christ is God, he has the dignity and glory to carry out the task, but it is performed in the nature of a human being. Thus, the incarnate Christ appeases God’s honor and justice.

Anselm writes:

“Therefore have we clearly found that Christ, whom we confess to be both God and man, died for us; and, when this known beyond all doubt, all things which he says of himself must be acknowledged as true.”1

Why Is This Book Worth Reading?

Cur Deus Homo is considered a philosophical and theological classic by one of Christianity’s greatest medieval thinkers. It offers a broad rationale for Jesus’s unique identity and work of salvation. While different in theological orientation from both the earlier church fathers and later Protestant Reformers, Anselm’s satisfaction theory is a bold and insightful defense of the faith.

Whether one agrees with all of St. Anselm’s doctrinal conclusions, his intuition that the incarnation makes the atonement possible makes this book a timeless philosophical and theological treasure.

I recommend this edition of Cur Deus Homo for further reading.


  1. Saint Anselm, Cur Deus Homotrans. Sidney Norton Deane (Fort Worth, TX: RDMc Publishing, 2005), 111.

Subjects: Books, Christian Literature, Reading

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About The Author

Kenneth R. Samples

I believe deeply that "all truth is God’s truth." That historic affirmation means that when we discover and grasp truth in the world and in life we move closer to its divine Author. This approach relies on the Christian idea of God’s two revelatory books - the metaphorical book of nature and the literal book of Scripture. As an RTB scholar I have a great passion to help people understand and see the truth and relevance of Christianity's truth-claims. My writings and lectures at RTB focus on showing how the great doctrinal truths of the faith (the Trinity, the Incarnation, the Atonement, creation ex nihilo, salvation by grace, etc.) are uniquely compatible with reason. This approach reflects the historic Christian apologetics statement - "faith seeking understanding." I work to help myself and others fulfill Peter's words in 2 Peter 3:18: "But grow in the grace and knowledge of our Lord and Savior Jesus Christ. To him be glory both now and forever! Amen." As an RTB scholar I have a great passion to help people understand and see the truth and relevance of Christianity's truth-claims. • Biography • Resources • Upcoming Events • Promotional Items Kenneth Richard Samples began voraciously studying Christian philosophy and theology when his thirst for purpose found relief in the Bible. He earned his undergraduate degree in philosophy and social science from Concordia University and his MA in theological studies from Talbot School of Theology. For seven years, Kenneth worked as Senior Research Consultant and Correspondence Editor at the Christian Research Institute (CRI) and regularly cohosted the popular call-in radio program, The Bible Answer Man, with Dr. Walter Martin. As a youth, Kenneth wrestled with "unsettling feelings of meaninglessness and boredom," driving him to seek answers to life's big questions. An encounter with Christian philosophy in Mere Christianity by C. S. Lewis led Kenneth to examine the New Testament and "finally believe that Jesus Christ is the divine Son of God, the Lord and Savior of the world." From then on, he pursued an intellectually satisfying faith. Today, as senior research scholar at Reasons to Believe (RTB), Kenneth uses what he's learned to help others find the answers to life's questions. He encourages believers to develop a logically defensible faith and challenges skeptics to engage Christianity at a philosophical level. He is the author of Without a Doubt and A World of Difference, and has contributed to numerous other books, including: Lights in the Sky and Little Green Men, The Cult of the Virgin, and Prophets of the Apocalypse. He has written articles for Christianity Today and The Christian Research Journal, and regularly participates in RTB's podcasts, including Straight Thinking, a podcast dedicated to encouraging Christians to utilize sound reasoning in their apologetics. He also writes for the ministry's daily blog, Today’s New Reason to Believe. An avid speaker and debater, Kenneth has appeared on numerous radio programs such as Voice America Radio, Newsmakers, The Frank Pastore Show, Stand to Reason, White Horse Inn, Talk New York, and Issues Etc., as well as participated in debates and dialogues on topics relating to Christian doctrine and apologetics. He currently lectures for the Master of Arts program in Christian Apologetics at Biola University. Kenneth also teaches adult classes at Christ Reformed Church in Southern California. Over the years Kenneth has held memberships in the American Philosophical Association, the Evangelical Philosophical Society, the Evangelical Theological Society, and the Evangelical Press Association. The son of a decorated World War II veteran, Kenneth is an enthusiastic student of American history, particularly the Civil War and WWII. His favorite Christian thinkers include Athanasius, Augustine, Pascal, and C. S. Lewis. He greatly enjoys the music of the Beatles and is a die-hard Los Angeles Lakers fan. Kenneth lives in Southern California with his wife, Joan, and their three children.

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