Who was St. Peter, according Benedict XVI
In this way, Peter initiates the Church’s Christological confession of faith. Though incomplete, his faith was nevertheless authentic and open – not a faith in something, but in someone; in Christ. Peter was not, however, free of human weakness, and in time he too betrays the Master.
The school of faith, then, is not a triumphal march but a journey marked daily by suffering and love, trials and faithfulness. Peter knew the humiliation of denial, and for this he wept bitterly. But having learned his own nothingness, he was then ready for his mission.That mission, made possible by our Lord’s acceptance of Peter’s fragile love and launched with the words "Follow me", is marked with hope: notwithstanding his infidelity, Peter knows the Risen Lord is at his side. His long journey in faith, constantly open to the Spirit of Jesus, renders him a credible witness; one who knows the true joy that lies in Christ, the way of salvation!"
(From the General Audience of May 24, 2006)