I can't believe it – but, yes, it's true. Madiba, who blessed us and the world so richly, is no more.

It seemed as if he had always been with us. Although he really only strode the world as a moral colossus after 1994, when he became president of South Africa, his stature had begun to grow while he was on Robben Island, when he became the most famous political prisoner of his time and inspired many to support the Free Mandela Campaign.

He was already being described in terms that made him seem larger than life. There were rumours that some in the ANC feared he would be found to have feet of clay, and so wanted him "eliminated" before the world was disillusioned. They need not have feared. Unbelievably, he exceeded popular expectations.

In his youth, he galvanised the ANC Youth League to ditch ANC national leaders who were thought to be too moderate, such as Dr AB Xuma. He repeatedly gave the apartheid security establishment the slip as the Black Pimpernel, holding up a finger to the regime and giving his community something to lighten the gloom of their existence.

I met Madiba once, fleetingly, in the early 1950s. I was training to be a teacher at the Bantu Normal College near Pretoria, which we jokingly referred to as "Bantu Normal College for normal Bantu", and he was the adjudicator in our debating contest against the Jan Hofmeyr School of Social Work. He was tall, debonair and cut a dashing figure.

Unbelievably, the next time I was to see him was 40 years later, in February 1990, when he and Winnie spent his first night of freedom under our roof at Bishopscourt in Cape Town.

Passive resistance campaign
Momentous events happened in those 40 years: the passive resistance campaign, the adoption of the Freedom Charter and the Sharpeville massacre on March 21 1960, which was seared into our collective consciousness. It told us that even if we protested peacefully we would be picked off like vermin and that black life was of little consequence.

South Africa was a land where public notices unashamedly announced “Natives and dogs not allowed’’. Our political organisations were banned; many of their members were banned, arrested or had gone into exile. These organisations would no longer operate non-violently – they had no option but to move to armed struggle. So it was that the ANC set up Umkhonto we Sizwe, with Nelson as its commander in chief. He had come to understand that the oppressed would not get their freedom as manna from heaven, and that oppressors do not give up their power and privilege voluntarily.

It would now be a treasonable offence to be associated with these banned organisations, which introduced the next chapter in the drama of our liberation – the Rivonia Trial.

With the free world we feared that Mandela and the other accused would be sentenced to death, as the prosecutor Percy Yutar demanded.

At the time, my family and I were living in London, where I was studying. Prayer vigils were held at St Paul's Cathedral and other locations in an effort to stave off the ultimate penalty.

Mandela's defence team tried to persuade him to moderate his famous statement from the dock, fearing that it might provoke the judge. But he insisted that he wanted to speak about the ideals he had espoused, for which he had striven, for which he had lived and for which, if need be, he was ready to die.

We breathed a monumental sigh of relief when the accused were sentenced to hard labour for life, even though it meant backbreaking toil in the lime quarry on Robben Island.

Sheer hell
The Robben Island period has sometimes been romanticised. In fact, it was sheer hell, especially for black convicts. White, coloured and Indian prisoners wore long trousers, shoes and socks and jerseys, while their black counterparts wore shorts and sandals whatever the weather and slept on thin mattresses on the concrete floors. They also had the worst diet.

The authorities were hell-bent on breaking the spirits of those awful "terrorists". There is a photograph that shows Nelson standing near Walter Sisulu who, along with several black convicts, did the mind-numbing job of sewing mailbags. Our future president did that! Many of the improvements, such as beds and study privileges, were thanks to pressure from Helen Suzman and the International Red Cross.

Some have said Mandela's 27 years in jail were a waste, suggesting that if had he been released earlier he would have had more time to weave his charm of forgiveness and reconciliation. I beg to differ.

He went to jail an angry young man, incensed by the miscarriage of justice in the travesty of the Rivonia Trial. He was no peace maker. After all, he had been MK commander and intended to overthrow apartheid by force.

The 27 years were absolutely crucial in his spiritual development. The suffering was the crucible that removed considerable dross, giving him empathy for his opponents. It helped to ennoble him, imbuing him with magnanimity difficult to gain in other ways. It gave him an authority and credibility that otherwise would have been difficult to attain. No one could challenge his credentials. He had proved his commitment and selflessness through what he had undergone. He had the authority and attractiveness that accompany vicarious suffering on behalf of others – as with Mahatma Gandhi, Mother Teresa and the Dalai Lama.

We were spellbound on Sunday February 11 1990 when the world came to a standstill and waited for him to emerge from prison. When he came out with Winnie by his side we were united in our admiration. What bliss to be alive, to experience that moment! We felt proud to be human because of this amazing man. For a moment, we all believed that it is possible to be good. We thought enemies could become friends, as we followed Madiba in the path of forgiveness and reconciliation exemplified by the truth commission and a polyglot national anthem, 11 official languages, and a government of national unity in which the last apartheid president could be a deputy president and a "terrorist" the head of government.

He was amazing
Madiba lived what he preached. Had he not invited his former white jailer as a VIP guest to his presidential inauguration? Did he not have lunch with Percy Yutar, the prosecutor at the Rivonia trial? Had he not flown to Orania, the last Afrikaner outpost, to have tea with Betsy Verwoerd, the widow of the high priest of apartheid ideology?

He was amazing. Who will forget his support for the retention of the Springbok emblem for rugby, although it was much hated by blacks? And that breath-taking gesture when he walked on to the turf at Ellis Park wearing a Springbok jersey to present Francois Pienaar the trophy for beating the All Blacks in the final of the 1995 Rugby World Cup, with the huge crowd of mainly Afrikaner spectators chanting "Nelson, Nelson …" And who could have believed that we would live to see the day when blacks in Soweto would be celebrating a Springbok victory, as they did in 1995?

Madiba was an amazing gift to us and to the world. He believed fervently that a leader is there for the led, not for self-aggrandisement. He was a prodigal spendthrift as he worked tirelessly to raise funds for schools and clinics in rural areas. While in office, he used some of his salary to set up the Nelson Mandela Children's Fund and later established his foundation for charitable works.

He was renowned the world over as the undisputed icon of forgiveness and reconciliation, and everybody wanted a piece of him. We South Africans basked in his reflected glory. We revelled in feeling good about ourselves. We even owe him for helping us get the bid to host the 2010 Fifa World Cup.

He paid a heavy price for it all. After his 27-year incarceration came the loss of Winnie. Soon after his release, Leah and I invited them for a traditional Xhosa meal at our Soweto home. How he adored his wife! All the while they were with us he followed her every movement like a doting puppy. He was quite devastated by their divorce. Thank God for Graça Machel – what a godsend.

Madiba really cared for people. One day I had lunch with him at his Houghton home. When we finished the meal he walked me to the door and called out: "Driver!" I told him I had driven myself from Soweto. He didn't say anything, but a few days later he phoned me to say: "Mpilo, I was concerned that you were driving yourself and asked a few of my business friends. One of them has offered to send you R5 000 a month to hire a driver!"

He could often be funny. His retort to my criticism of his taste in gaudy shirts was: "It's pretty thick coming from a man who wears a dress in public."

He showed remarkable humility when I criticised him publicly for living with Graça without the benefit of matrimony and setting a bad example. Some heads of state would have excoriated me. Soon afterwards I received an invitation to his wedding.

Our world is a better place for having had a Nelson Mandela, and we in South Africa are that bit better. How wonderful if his successors were to emulate him and if we were to value the great gift of freedom he won for us at the price of so much suffering.

We thank God for you, Madiba. May you rest in peace and rise in glory.