Under African skies, from every region of the earth, lifting faces to hot sun and teeming rain, we sloshed through sudden streams and mud on the otherwise green magnificent campus of the University of Zimbabwe. Never far away was the awareness that this country's natural resources have been stupidly squandered by political mismanagement and that one in three local people is likely to be carrying the HIV virus.

Over these December weeks nearly 5,000 Christians of all denominations, among them large numbers of young people, have gathered in Harare for the Golden Jubilee assembly of the World Council of Churches (WCC), the eighth since the first in Amsterdam in 1948.

At the opening ceremony a giant teak cross, carved by Zimbabwean David Matasa, was borne aloft through the multi-coloured congregation to a riotous assembly of drums and voices, reflecting the beauty and pain of this extraordinary continent.

The cross depicted the suffering face of Africa's peoples, brought low by colonialism, economic exploitation and corruption, and the hopelessness of millions of refugees from terror and starvation. But the huge cross spoke also of Africa's indomitable struggle for liberation and the spiritual hope of her communities and nations. Pain and beauty met together in solidarity.

In the opening ceremony Puerto Rican pastor Eunice Santana spoke of Mother Africa as the place where the words of Jesus take on a unique rhythm and flavour. "Mother Africa, so easily forgotten by the powerful, where the same Jesus received asylum as an infant 2,000 years ago," she mused.

Each of the keynote speakers called for a worldwide momentum to cancel the unsustainable debt of the poorest nations. Such nations have long since paid their debts with their lives and the lives of their children. Twelve hundred women at a pre-assembly meeting also demanded debt cancellation as a human-rights issue.

They pointed to the direct and devastating effects of IMF and World Bank structural adjustment policies in the erosion of family life, failing educational and health services and increased child abuse.

"Let us dare to be prophetic," a speaker urged, "let us get dirt on our hands, the dirt of the poor, of the children who sleep on the streets . . . of small farmers who have lost their land; let us get dirt on our hands by reaching out and holding the hand of the other, the one who challenges our truths and our certainties."

She was speaking of Brazil but her words reminded me of my hurrying past prone bodies in Wicklow Street in Dublin and of the resistance of the majority of our Christian people to mixing and mingling with those who "dig with the other foot" for fear of losing purity or blurring the clean lines of denominational identity.

Two other speakers might easily have been speaking of Ireland. The Albanian Orthodox Archbishop Anastasios spoke on memory and identity, while Kosuke Koyama, the celebrated Japanese author of Water Buffalo Theology, made hope his theme. In our world, he said, "racism is visible. Machineguns are visible. Starved bodies are visible."

Rulers so often seek to make such realities invisible. But the Gospel insists on making the invisible visible. In the Gospel hope breaks through because "grace causes commotion, not tranquility" and it calls us to a two-way traffic, offering hospitality to the stranger but also accepting hospitality from strangers.

I thought of the current hearings in the North where those who have most deeply suffered are seen, heard and rendered visible, often for the first time, and of the need for all of us to modify our sharp-edged political agendas. Perhaps it is necessary now to see things blurred, as one speaker put it, to see the world through the tears in our eyes.

And what of the future of the ecumenical movement? Is unity still a vision that inspires? Is ecumenism in crisis? Certainly there are critical issues to be confronted, particularly arising from the vocal complaints of Eastern Orthodox churches and discomfort with the undue western liberal influence on ecumenical relations and democratic forms of decision-making.

Some notables have absented themselves from the assembly, or merely sent representatives. Patriarch Bartholomew did send a substantial message of greeting. Conflicting approaches to the ordination of women and contentious issues of human sexuality (homosexuality in particular) add fuel to the smouldering discontent. Some hard talking and deep listening will be necessary in the days to come.

The Roman Catholic Church still remains outside the official membership of the WCC, though warm congratulations from Pope John Paul II were conveyed to the assembly by Cardinal Mario Conti, head of the official Vatican delegation. Most memorable, however, were the words of the Roman Catholic Archbishop Paride of Sudan, guest preacher at the assembly's Africa Celebration event in the Rufaro football stadium.

Like some desperate voice in the wilderness he pleaded for the million starving refugees in his land; he told of the daily air strikes from Khartoum on defenceless villages. "Can anyone help me? Can you delegates of the WCC from all over the world help us live in peace like brothers and sisters?" he asked. He particularly urged delegates from Europe and the US to use their influence as they had for Kosovo in securing a "no-fly zone" over Southern Sudan.

Is not this the real ecumenical challenge for the 21st century? There is no measuring that kind of suffering except in equal measures of hope and solidarity. Feeling the pulse of hope in that football ground, there was no doubting for this Northerner that the centre of gravity of the Christian church has shifted to the south, that the heartbeat of the Body of Christ is now in Africa.

Sister Geraldine Smyth is director of the Irish School of Ecumenics.