The increased focus on blood ties into the Medieval tendency of concomitance—the mistaken belief that a part is equal to the whole, Bynum said.

This belief made it possible for people in the Middle Ages to believe in relics and that one’s “neighbors were subsumed into one’s own suffering,” Bynum said. “However, they were not sure how far they could spread their suffering to others.”

Bynum concluded by saying that these themes, which first appear in the late Middle Ages, are still present in perceptions of Christianity today.

“Today theologians find it difficult to think behind Medieval ideas of Christianity,” Bynum said. “It is difficult for non-Christians or post-Christians to see that Christianity has not always been this way.”

Bynum is currently a professor of European medieval history at the Institute for Advanced Study in Princeton, NJ and is a university professor emerita at Columbia University. She taught for seven years at Harvard, holding posts in the history department and at the Harvard Divinity School.

Bynum received her doctorate from Harvard University in 1969.

—Staff writer Ella A. Hoffman can be reached at ehoffman@fas.harvard.edu.