The secular world may have thought it was done with theology, but theology was not done with it. Recent decades have seen a resurgence of religion on the social and political scene, which have driven thinkers across many disciplines to grapple with the Christian theological inheritance of the modern world. Adam Kotsko provides a unique guide to this fraught terrain. The title essay establishes a fresh and unexpected redefinition of theology and its complex and often polemical relationship with its sister discipline of philosophy. Subsequent essays build on this framework from three different perspectives. In the first part, Kotsko demonstrates the continued vibrancy of Christian theology as a creative and constructive pursuit outside the walls of the church, showing that theological concepts can underwrite a powerful critique of the modern world. The second approaches Christian theology from the perspective of a range of contemporary philosophers, showing how philosophical thought is drawn to theology even despite itself. The concluding section is devoted to the unexpected theological roots of the modern world-system, making a case that the interplay of state and economy and the structure of modern racial oppression both build on theological patterns of thought. Kotsko’s book ultimately shows that theology is not a scholarly game or an edifying spiritual discipline, but a world-shaping force of great power. Lives are at stake when we do theology—and if we don’t do it, someone else will.