How much of what we call "basic morality" is actually inherited from Christianity? Bart Ehrman joins Michael Shermer for a wide-ranging conversation about one of the biggest moral questions in history: why do we feel obligated to care for strangers at all?

Drawing from his new book Love Thy Stranger, Ehrman argues that the idea of helping people outside your tribe, family, or nation was not a moral given in the ancient world. Greek and Roman ethics made room for loyalty, friendship, and civic duty, but not for radical concern for the outsider. He makes the case that Jesus changed that moral equation—and that his teachings still shape the modern West, including many people who no longer consider themselves religious.

The conversation also covers Ehrman's own path from evangelical Christianity to agnostic atheism, the problem of suffering, whether pure altruism really exists, and the difference between forgiveness and atonement.

Bart Ehrman is the James A. Gray Distinguished Professor of Religious Studies at the University of North Carolina, Chapel Hill, and The New York Times bestselling author of Misquoting Jesus and How Jesus Became God. His new book is Love Thy Stranger: How Jesus Transformed Our Moral Conscience.