Although interest in the theology of Karl Barth is greater today than at any time since his death, Barth's moral thought continues to be widely misunderstood. This groundbreaking study of the twentieth-century's most important Christian thinker offers the first treatment of Barth's ethics from a Roman Catholic perspective. Focusing particularly on Barth's 'ethics of creation' in the Church Dogmatics, Rose reclaims Barth from a number of misinterpretations and presents Barth's account of the good life within his distinctively Christian metaphysics. Among the most provocative of Rose's claims is that Barth sees the Christian life as guided by reason and nature, an interpretation that finds Barth in conversation with ancient and medieval ethical theories about the nature of human happiness. A significant contribution to Barth studies and current debates in contemporary Christian theology, Ethics with Barth sheds valuable light on the connection between metaphysics and ethics, the trinitarian dimensions of Christian moral thought, the nature of the divine good, the role of Christian philosophy, Barth's conception of moral reasoning, and his views on eudaimonism and the natural law.