Ask what principle Martin Luther put at the center of his Protestant Reformation theology, and you’ll get several good answers: justification by faith alone; the primacy of scriptural authority over ecclesial authority; the theology of the cross. Philip Cary offers another answer to that question, one that is distint from yet fundamentally connected to those other answers. In his book The Meaning of Protestant Theology, Cary traces the steps of Luther’s theology to their roots in St. Augustine, showing how the self-consuming introspective turn inherent to the Augustinian way is overcome when Luther discovers the power of the Gospel as an external Word that gives us Christ. In this episode of Christian Humanist Profiles, David Grubbs interviews Dr. Phillip Cary, professor of philosophy at Eastern University and author of The Meaning of Protestant Theology: Luther, Augustine, and the Gospel that Gives Us Christ (Baker Academic, 2019).