At a service in Christ Church, Oxford, last Sunday, USPG: Anglicans in World Mission began its celebrations for the creation 150 years ago of the Universities Mission to Central Africa (UMCA), which merged with the Society for the Propagation of the Gospel in Foreign Parts in 1965.

In his sermon the Bishop of Southwark, the Rt Rev Tom Butler, who served as a USPG missionary in Zambia in the 1970s, recalled David Livingstone's Oxford lecture in 1857, followed up by one in Cambridge where he said: "I go back to Africa to try to make an open path for commerce and Christianity. Do you carry out the work I have begun? I leave it with you".

Bishop Butler traced the story of the first UMCA missionaries in which reality frequently failed to match the vision: "In the latter years of the nineteenth century or indeed the early years of the twenty-first century, it doesn't do to view mission here or overseas with rose coloured spectacles, for true mission, living in the gap between vision and reality can be a costly business."

He went on, "It may be fashionable to criticise those missionaries, but they were people of great faith and commitment. They knew that they were going to almost certain death and yet they went, confident in the love of God and the power of Christ's gospel and they planted the seeds of faith which have blossomed into strong Anglican churches around the globe."

Today, said the Bishop, mission agencies faced new challenges. "We've been told for decades that the era of sending out missionaries from this country overseas has well ended and is even paternalistic, although I don't hear this from the churches overseas, who knowing the challenges they face, are more than ready to welcome mission partners from elsewhere, just as our mission in this country is strengthened by partners from other parts of the globe.

"And the mission story is more complicated. It's one thing for past generations to be challenged to give generously to send a missionary to heal the sick and preach the gospel in lands where the Lords name is unknown, it is quite another and more sophisticated story to support mission from everywhere to everywhere".

Bishop Butler continued by saying that Livingstone's vision, with its four strands of healing, education, commerce and Christianity, is alive today in the Anglican churches of the UMCA area which USPG continues to support.

Christians are bringing healing through the likes of St Francis' Hospital in Katete, Zambia, and the work of USPG mission companion Dr Shelagh Parkinson, who started the HIV clinic there four years ago.

Education, including theological education by extension, environmental planning and leadership training to better equip lay and ordained church leaders is also being undertaken to build the capacity of the church to carry out God's mission.

"Livingstone, with his emphasis on commerce, would surely have approved of USPG's programme of loans for income generation enabling Central African dioceses to set up projects that will give the church long term sustainability," remarked Bishop Butler.

He added that it would be "quite untrue to believe that missionaries, or mission companions as they're called today, no longer go from the Church of England to central Africa", listing the hospital workers, development workers, youth workers, parish priests and even two bishops who are supported by USPG.

"And in days when giving to mission agencies is modest, it's interesting to see that these missionaries, like their Victorian forebears themselves raise much of the funds which enable them to fulfil their calling. I'm not sure whether we should be proud of their commitment, or ashamed of the level of our giving which make it necessary," he said.

The Bishop concluded his address by making the link between mission work and the current state of the Anglican Communion, and stressing that the Lambeth Conference must take place.

"We still live in the gap between vision and reality, and there are still people prepared to give their lives to seek to close that gap in mission and we in England will have the opportunity of meeting many from the global Anglican mission field next year with the advent of the Lambeth Conference, if it happens, as it certainly should," he said.

"For it would be obscene that with so much human need crying out for attention around the globe, if the Church cancelled or postponed its conference because of arguments on such fractious matters as homosexuality.

"The Lambeth Conference next year could be really significant if the bishops paid attention to what really matters, and we will deserve God's judgement if we don't."

The celebrations move to Cambridge next year for the actual founding of UMCA, and then to Malawi in 2011 to commemorate the arrival of the first missionaries led by Bishop Mackenzie.