Rainbow nation's guiding light retreats into the shadows

Desmond Tutu, one of the great figures in the history of modern South Africa, has retired from public life. Paul Vallely salutes him

One of the great figures of the 20 century vowed he was going into retirement yesterday. Do not believe it. Desmond Tutu has retired before, and whenever a serious injustice has reared its head he has returned.

Desmond Mpilo Tutu was one the central forces in the dismantling of apartheid. Over the years the white regime had responded to protest and resistance by arresting tens of thousands of black activists. Many more in the African National Congress (ANC) had gone into exile, to continue their opposition from abroad.

The torch of resistance passed to the South African churches, the one group the white government could not outlaw. Its most prominent leader was Desmond Tutu, who in 1975 had become the first black man to be appointed Dean of St Mary's Anglican Cathedral in Johannesburg. "It was people of faith who by and large kept the fires of revolution burning," he later told me for a BBC documentary. He came to international attention for his vigorous condemnations of the massacre of schoolchildren in Soweto. Tutu spoke out, encouraging a Western economic boycott of South Africa. Sanctions might throw blacks out of work, Tutu argued, but at least they would be suffering "with a purpose". He travelled abroad, raising an international outcry. And his behind-the-scenes visits to powerful financial institutions in the US helped to encourage disinvestment. In 1984, he was awarded the Nobel peace prize. Two years later he was made Archbishop of Cape Town. Desmond Tutu had a shrewd understanding of how to play politics at an international level because he had spent so much time in the UK. He took his theology degrees at King's College London in the 1960s. His first job was as a curate in Golders Green.

His exposure to Western media taught him how best to use it. He became so well known, he once told me, that when he met a hermit nun in California she told him that the first thing she did each morning was to pray for him. "I am being prayed for by a nun at 2am in the woods in California each day: what chance does the apartheid government stand!"

But his astuteness extended to politics too. When a new white president, F W de Klerk, took over in 1989 Tutu assured him that, if there was change, the blacks would not turn on the whites. Within a year De Klerk had released Nelson Mandela, who spent his first night of freedom in the home of Desmond Tutu.

Tutu did not escape criticism for his pledge. Some in the black community asked by whose authority he gave such a promise. He made his reply at the funeral of the South African Communist Party leader Chris Hani in 1993, when he spurred a crowd of 100,000 into chanting, over and over, "We will be free!", "All of us!", "Black and white together!".

Then he finished his speech with a quote that was to resonate around the world: "We are the rainbow people of God! We are unstoppable! Nobody can stop us on our march to victory! We are moving to freedom and nobody can stop us! For God is on our side!" Two things were on display. Tutu's extraordinary bravery. But also his unshakeable faith in the intrinsic goodness of human beings. His latest book, written with his daughter, Mpho, is called Made for Goodness: And Why This Makes All The Difference. To the public Desmond Tutu is a highly political priest, but those who meet him see first a deep spirituality.

He tells a great story: "When the missionaries came they had the Bible and we had the land. And they said 'Close your eyes and let us pray.' And we dutifully did so, but when we said 'Amen' and opened them, we had the Bible and they had the land." Perhaps, he says, it was not such a bad deal.

His belief in God is what motivates his every action, and his amazing bravery. He once waded into a crowd in a township where a police informer was about to be "necklaced" – set alight with a petrol-filled tyre around his neck – and rescued the man. He later made a public announcement that if the practice did not stop he would leave the country. Astonishingly, it stopped. But his Christian faith is more than personal. It inspired the creation of the Truth and Reconciliation Commission, of which he was appointed head in 1995, in an attempt – largely held to have been successful – to bring healing to the divided white and black communities. It offered amnesty to anyone who would come forward and confess their crimes in the apartheid era, and in the resistance to it, and ask for forgiveness.

He has spoken truth to power repeatedly, condemning human rights abuses in Mugabe's Zimbabwe, criticising Israel's treatment of the Palestinians and attacking homophobia in his own church. He has condemned the war in Iraq and said detention without trial at Guantánamo Bay is "utterly unacceptable." He lamented the election of Pope Benedict XVI because of his opposition to the use of condoms in the fight against Aids in Africa. He has preached that global warming is a insult to the Creator.

Even when diagnosed with prostate cancer in 1997 he did not give up but convened Nelson Mandela, Jimmy Carter and others to form The Elders, a group who would help resolve international problems. "Desmond Tutu's voice," said Nelson Mandela recently, "will always be the voice of the voiceless."

Desmond Tutu is a man who laughs and cries easily, but also a man of huge imagination, sensitivity, humility and wisdom. Asked to sum up his message he once said: "Goodness is stronger than evil; love is stronger than hate; light is stronger than darkness; life is stronger than death." His work is not finished yet.

The next moral leaders of the nation

Zwelinzima Vavi

Heads up the Congress of South African Trade Unions (COSATU), which is the country's largest labour federation. He played a role in President Jacob Zuma's rise to power but has recently spoken out against government corruption. There has been talk that he will run for office at some point.

Kumi Naidoo

Brought up in Durban and involved in the struggle against apartheid from an early age, Kumi Naidoo was arrested a number of times before leaving for the UK in 1987. He studied in Oxford as a Rhodes scholar before returning home following Nelson Mandela's release. Last year he became the first African executive director of Greenpeace.

Helen Zille

The leader of the opposition Democratic Alliance party, in 1977 Helen Zille – at the time a journalist – uncovered the murder whilst in police custody of anti-apartheid campaigner Steve Biko. She later became mayor of Cape Town, was awarded the World Mayor award in 2008, and is currently the premier of the Western Cape.

Zackie Achmat

South Africa's most prominent Aids activist and the founder of the Treatment Action Campaign, which fights for better access to treatment, care and support for people with the disease in the country. Zackie Achmat is HIV-positive and for years refused to take antiretroviral drugs until they were made available to everyone for free.