In his address, Professor Calhoun used American Christian abolitionism to illustrate the beneficial role that religion can play in political debate. Surveying the past two millennia, I argue that Christian political thought has protected liberty in every era of the church’s dramatic history. Along the way, I rebut critics—from the left and right—who urge that Christianity’s political influence has been unhelpful or harmful. I also seek to show that statements like “religion has no place in politics” are best understood as expressions of arbitrary bias.