Based on a comprehensive reading of his entire work, in this book Jens Zimmermann presents Bonhoeffer’s theological ethos as a Christian humanism, that is, as an understanding of the gospel rooted in apostolic and patristic writers who believed God to have renewed humanity in the incarnation. The heartbeat of Bonhoeffer’s Christianity that unifies and motivates his theological writing, his preaching, and his political convictions, including his opposition to the Nazi regime, is the conviction that Christianity as participation in the new humanity established by Christ is about becoming fully human by becoming Christlike. In eight chapters, the author details Bonhoeffer’s humanistic theology following from this incarnational starting point: a Christ-centered anthropology that shows a deep kinship with patristic Christology, a hermeneutically structured theology, an ethic focused on Christ-formation, a biblical hermeneutic centered on God’s transforming presence, and a theological politics aimed at human flourishing. In offering a comprehensive reading of his theology as Christian humanism, Zimmermann not only places Bonhoeffer in the context of the patristic and greater Christian tradition but also makes apparent the relevance of Bonhoeffer’s thought for a number of contemporary concerns: hermeneutic theory, the theological interpretation of the Bible, the relation of reason to faith, the importance of natural law, and the significance of religion for secular societies. Bonhoeffer turns out to be a Christian humanist and a modern theologian who models the deeply orthodox and yet ecumenical, expansive Christianity demanded by our time.