You might not realize it at first, but if you’re passionate about church renewal, A Thicker Jesus: Incarnational Discipleship in a Secular Age (Westminster/John Knox, 2012) is the book you should read. Why? Because it’s about theology, not about technique.

Glen Harold Stassen is the Lewis B. Smedes Professor of Christian Ethics at Fuller Theological Seminary where he has taught since 1997. The author of several books, he has received several excellence in teaching awards. He is also a member of the Nuclear Weapons Freeze Campaign, and the Strategy Committee of Peace Action, the largest grass-roots U.S. peace organization. Stassen is the son of Harold Stassen, the progressive Republican candidate for the Presidency from Minnesota. He acknowledges his roots and his aims for this book in its Preface. “I deeply believe churches need renewal,” he asserts and aims to write for “ordinary people” so as to stimulate their thinking and renew their faith.

A Thicker Jesus thus posits a path to church renewal—a theological path which is a refreshing voice amidst the plethora of attempted renewal-through-restructuring-schemes approaches. What’s needed in this secular age (building on the work of Charles Taylor), Stassen maintains, is a rediscovery of a holistic theology of Jesus, what he calls “a thicker Jesus.” And although it may prove to be rather tough going for some “ordinary people,” it is well worth the time and effort to follow his argument and dwell in his many examples and stories. A Thicker Jesus is beautiful and compelling. It invites the reader to enter into the stories of Dietrich Bonhoeffer, André Trocmé, the Barman Declaration, Martin Luther King, Jr., and Clarence Jordan, Dorothy Day, and Muriel Lester. These are saints the church should know and emulate.

Why? Because, Stassen argues, their witness reveals what it means to be a disciple of Christ in a time of historical testing. If the church is all too often tempted to peddle a wimpy Jesus, a touchy-feely Jesus, a private, personal Jesus, these saints follow “a thicker Jesus,” in Stassen’s parlance, a Christ Jesus who is Lord of all life. Their incarnational discipleship, Stassen maintains, was a regular practice, not a theoretical ideal. These heroes of faith, he reveals, lived out the faith in ways that made real their theology and faith in the public arena, around the most critical issues and challenges of their time. This is what he calls “public ethics” and it is, in his view, the church’s response to the dynamics of a secular age.

The lives of these heroes of faith reveal glimpses into the concreteness of living and acting as disciples in the context in which they are placed. But not resting content with some sort of romanticization of martyrs, Stassen uses their witness as a springboard into a more complete and compelling understanding of discipleship.

This he calls “incarnational discipleship.” In his framework, this is a historically-embodied, thick, realistic, engaged, holistic call for repentance from all that would thwart God’s kingdom—racism, nationalism, greed, and so forth—into an engaged commitment to Kingdom values.

If you have asked where to find a faithful and solid identity for faith and ethics, read on. If you have wondered how Christian identity can be a compass in a rapidly changing culture and secular context, read on.

In Stassen’s view, Incarnational Discipleship happens within communities of faith. It produces the fruits of the Holy Spirit. It witnesses to the work and person of Jesus. It generates a way of faithful thinking and living in response to this secular age. It is grounded in the Sermon on the Mount and in the life and person of Jesus.

A Thicker Jesus requires pastors and church leaders to explore where, how, in what ways, and to what ends, God’s grace enters incarnationally into the midst of our hiding, into the midst of our lives, into the midst of our witness. This will empower the church, Stassen reveals, to meet the challenges of the secularism of the twenty-first century.

I conclude with Stassen’s concluding challenge and invitation: “Will you join in the apostolic witness to a thicker Jesus—in the tradition of incarnational discipleship?” (p. 221)

Let our renewal begin.