There is the old saying that goes something like: "God does not call the prepared, He prepares the called." Trite perhaps, but it is something for us to keep in the back of our minds and something that Augustine reminds me of.
As a saint we honor him for his obedience and compassion and as a human we can learn from his lack of self-confidence and humanity. So many of the things that resulted from his weakness in the end shine in his work, even if they did not come to fruition until long after his death.
He was afraid; he had trouble making decisions; he failed to reconcile people, who while they shared a single belief in Jesus, held opposing views as to the value of being victors and of being invaded, and on liturgical practices. Yet he ultimately held fast to the mission of his vocation and relied not on his own strengths but on the Lord. His gentleness and compassion managed to let Christ's love spread and Church grow in England, allowing the understanding of the people to be transformed into an understanding of Christ, without loss of dignity or custom.
Augustine reminds us that we cannot let our weaknesses and sinfulness keep us from doing the will of God nor must we take pride in our accomplishments or despair from our failures.
Your brothers know and are used to the Roman Church, in which you have been nurtured. But I approve of your selecting carefully anything you have found that may be more pleasing to Almighty God, whether in the Roman Church or that of Gaul, or in any Church whatever, and introducing in the Church of the Angli, which is as yet new in the faith, by a special institution, what you have been able to collect from many Churches. For we ought not to love things for places, but places for things. Wherefore choose from each several Church such things as are pious, religious, and right, and, collecting them as it were into a bundle, plant them in the minds of the Angli for their use.
-- From a letter of Gregory the Great to Augustine of Canterbury