When Steyn was assigned to Mandela's protection it was no more than a formal administration handover from one presidential term to the next.
Steyn, like all the other white bodyguards assigned to Mandela, was expecting his marching papers within the week. Instead what he got was a five-year, unobstructed view of a man that could heal a nation - and himself - up close.
Steyn's transformation began with the simplest and most basic of things: good manners.
Steyn saw that Mandela never walked past women or children without greeting them. Everyone was treated the same, irrespective of their colour, age, gender or social position.
As he observed Mandela during those first few weeks, he expected to see the cracks, but eventually came to the conclusion that the president was genuine.
"When I started working for Madiba, for the first time I was recognised as somebody, not a second-class citizen," Steyn says. "The previous president barely tolerated us, but Madiba would always thank us, and make us feel like we were doing something vitally important. And there I was, this white racist who had once wished him dead, and yet he was able to put the past behind him and treat me as an equal."
The president's bodyguards found themselves living a surreal existence. Sometimes they would occupy the grandest of hotels, palaces or presidential guest houses as Mandela toured the world. And suddenly they would be preparing for the president to tour a poverty-stricken village, or make visits to patients at hospital wards, without the press ever knowing.
"Madiba was one of those rare exceptions," Steyn says. "He was incredibly humble, and seemed to thrive whenever he was called upon to mingle, especially if it meant spending time with those suffering from hardships."
Steyn was with Mandela when, in 1995, as a special guest of former US president Bill Clinton, Mandela was in New York to attend the 50th anniversary of the United Nations.
Mandela took his usual 5am walk in Central Park. Then he saw a homeless person in the darkness ahead of him. To the horror of the Secret Service, the president deviated from his course and made to go over and greet the man. He was blocked by the anxious Americans, but the South African bodyguards knew resistance was futile and, eventually, Madiba talked them all into paying one homeless soul the visit of a lifetime.
Mandela was often instructed by his doctors to forego his official duties and get some rest in Qunu, his hometown. But invariably there would be a knock at the door - usually one of the elders asking for assistance in resolving a local dispute. There he wasn't the president, but rather a senior member of the local clan who had a duty to assist in the issues of the village.
"It's almost as if they were unaware of the power of this international statesman," adds Steyn. "[It was] hardly the stuff of presidents, but a measure of the man."
One sleepless night after speaking with some homeless street kids in Cape Town, Mandela decided to give one third of his presidential salary toward a fund that could deal specifically with children, and this became the Nelson Mandela Children's Fund. Every year for his birthday, Mandela would host a huge children's party for those especially poor or sick.
He was 95 years old when, last year on December 5, the world said its goodbyes. Steyn says: "The late Mr Nelson Mandela followed three rules throughout his own personal journey; free yourself, free others, and serve everyday - it was not just his mantra, it was his way of life."
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