St. Augustine, the Teacher, is possibly the best example of how faith in Christ changed a person. Augustine's narrative of personal transformation in his book Confessions provides a template for life in Christ that still rings true today.
St. Benedict, the Monk. Many would argue that St. Benedict, the Monk, contributed more to saving western Christian culture than anyone else. Born just after Rome fell, Benedict founded the religious community that would, in time, preserve the best of the old and allow for the emergence of an authentic, Christian way of life.