Pope Benedict XVI came from a Catholic Bavarian town. Childhood family jaunts included trips to the shrine of the Black Madonna, Our Lady of Altotting. He entered the seminary at the age of 13. He became a priest, scholar and theologian. He lived his life in service to the church. Even in resigning from the papacy, he embraces the monastic life to pray for a church he has ever loved.

With hindsight, his visit to the tomb of 13th century Pope Celestine V, a Benedictine monk who resigned from the papacy eight centuries before, becomes poignant.

In 2009, on a visit to Aquila, Italy, Benedict left at Celestine's tomb the pallium, a stole-like vestment that signifies episcopal authority, that Benedict had worn for his installation as pope. The gesture takes on more meaning as the monkish Benedict steps down.

We expect the pope to be perfect. Catholics hold him to be the vicar of Christ on earth. He stands as a spiritual leader for much of the world. Statesmen visit him from around the globe. He lives among splendid architecture, in the shadow of the domed St. Peter's Basilica. All testify to an almost surreal omnipotence.

In this world, however, walked a vulnerable, human person. And in a paradox of life, his most human moment -- giving up the power of office -- may prove to be his most potent, delivering a message that, as St. Paul noted many centuries ago, "Power is made perfect in infirmity."