As the season of Advent begins, the departing Archbishop of Canterbury has urged Anglican Communion leaders to keep Jesus Christ, who sustains the Church, as their focus.

After nearly a decade of service, in his last Advent letter on Sunday to the Primates of the Anglican Communion and Moderators of the United Churches, the Rev. Rowan Williams began with a quote from Colossians 3:4.

'Your real life is Christ and when he appears, then you too will appear with him and share his glory!"

He warned leaders about putting their focus on the Church's works instead of Jesus.

"When we try to pretend that the holiness of Jesus is triumphantly visible in the Church, we are in danger of turning our minds away from the fact that the enduring power that sustains the Church is Christ alone, not our measures of success or coherence," he said.

However he added that in the Church could be seen a hope that comes from Jesus.

"But it is still true that – as Paul can say elsewhere, in II Corinthians, for example – the glory of the future can be seen from time to time in lives that are fully turned to the face of Jesus," he added.

He urged leaders to keep both insights in mind.

"The treasure of gospel is in earthenware pots, yet the glory of Christ can be seen in human faces. We have not arrived at the end of all things, but we long for it because we have seen something of its radiance and joy in the life of the Christian community and its worship and service."

He said that in the past ten years, the Anglican Communion has endured "much suffering and confusion and still lives with this in many ways; yet we are still privileged to see the glory of God in the face of Jesus Christ in different ways within our common life, and so are reminded by God's grace that it is still Christ who lives secretly at the heart of our fellowship, and renews it day by day."

He described his view of the Communion's decentralized nature and checks and balances.

'[O]ur communion has never been the sort of Church that looks for one central authority. This doesn't mean that we are not concerned with truth or holiness or consistency. It simply acknowledges that all forms of human power and discipline can become corrupted, and that in the Church we have to have several points of reference for the organizing of our common life so that none of them can go without challenge or critique from the others."

"Our hope is that in this exchange we discover a more credible and lasting convergence than we should have if someone or some group alone imposed decisions – and that the fellowship that emerges is more clearly marked by Christlikeness, by that reverence for one another that the Spirit creates in believers."

The Rev. Williams described two of the Communion's recent leadership meetings, what brought them together, and where Christ could be seen.

"In the work done around evangelism, healthcare, the environment, the rights and dignities of women and children and of indigenous peoples and many more areas, what drew people together was this halfway formal model of a global community of prayer and concern maintained by deep friendship and common work," he said.

"This is where you are probably most likely to see the beauty of the face of Christ in the meetings of the Communion; this is where the joyful hope of Christian believers is most strongly kindled. And this also reminds us most forcefully of the fact that what we aspire to as Anglicans is not to be a federation of loosely connected and rather distant relatives who sometimes send Christmas cards to each other, but a true family and fellowship in which we share our hopes and know that we are responsible for each other's well-being and integrity before God."

He said that while he leaves his leadership position with much work "left undone and unresolved ... there is also a great sense of thanksgiving and celebration for the many moments when the hidden Christ has shown his face for an instant in the holiness, the common witness, the service or the suffering of faithful Anglicans in so many places."

"In saying goodbye as Archbishop of Canterbury, I want also to say thank you to God for these moments and the friendships that surround them, and thank you also to all with whom I have had the privilege of ministering in this decade in every province of the Communion," he added.

He called incoming Archbishop of Canterbury, the Rev. Justin Welby an "outstanding servant of God" and said he knew he and his family would be in their prayers.

"To all of you, as you prepare to celebrate the coming of the Lord, I wish every blessing and the 'crown of uprightness' promised to 'all those who have longed for his appearing' (II Timothy 4.8)."