When I lecture on the First Crusade in my courses at Florida State College at Jacksonville, I occasionally get a question from one of my students along the lines of “How could Christians do this?”

They ask because, as modern Christians with a post-Enlightenment understanding of their faith, they find the idea of God- or Jesus more specifically- supporting warfare to be troubling. Such students tend to associate New Testament Christianity with peace as Jesus himself famously called on others to turn the other cheek when confronted with violence. Often, in such cases, students will cite the biblical commandment “Thou shalt not kill” (Exodus 20:13) as a proof-text supporting their assumptions that medieval Christians who participated in the crusades simply did not understand the Bible.

I find I often have to restrain myself a bit when I respond. Not because I am upset with the student, of course, but because I feel tempted to cover too much in my response. There are a number of assumptions here that are either demonstrably false or (at the least) highly debatable, but among the most significant, perhaps, is the idea that Exodus 20:13 represents a biblical injunction against “killing.” There are two major problems with this assumption. Continue reading →