Hardly a week goes by in which parishioners do not grill me about my friendly openness to Islam. They believe that the Qur'an not only permits violence but mandates it. Almost as frequently, I receive hard in­quiries about why we should bother with the Old Testament, which seems to be riddled not just with warfare but with divinely sanctioned warfare. I counter both challenges in various ways, but I had never thought to explore how the two questions might actually be one.

Leave it to the astonishingly productive Philip Jenkins to lay the groundwork for such an exploration. If I run a search for Jenkins's publications, I am not sure whether to shudder, chuckle or drop my jaw in awe. Terms like polymath, outlier and wunderkind come to mind when I notice that he has written on early christological battles, styles of Christianity in the Southern Hemisphere, hidden gos­pels, sexual abuse in Catholicism, cults, Native American spirituality, Europe's religious crisis, the histories of Wales and the United States, and even criminal justice, pornography and terrorism. The common thread among these diverse topics—except, perhaps, the history of Wales—is that these are subjects that matter not only to scholars but to citizens of the world.

A cynical little demon perched on my shoulder as I began reading Laying Down the Sword, which is more Old Testament exegesis and hermeneutics than anything else. Old Testament is my field; surely he can't have mastered that too. But Jenkins's scholarship is reasonably well informed, with no major gaffes, and the interdisciplinary edge he brings to the task makes his analysis quite insightful. For example, his background in sociology helps him to explain what happens to a community when its scriptures create cognitive dissonance and ethical dilemmas.