Christians have sometimes professed that the church ought to be "in the world but not of it," yet the meaning and significance of this conviction has continued to challenge and confound. In the context of persecution, Christians in the ancient world tended to distance themselves from the social and civic mainstream, while in the medieval and early modern periods, the church and secular authorities often worked in close relationship, sharing the role of shaping society. In a post-Christendom era, this latter arrangement has been heavily critiqued and largely dismantled, but there is no consensus in Christian thought as to what the alternative should be. The present collection of essays offers new perspectives on this subject matter, drawing on sometimes widely disparate interlocutors, ancient and modern, biblical and "secular." Readers will find these essays challenging and thought-provoking.