Nelson Mandela was described as a towering figure as the United Nations General Assembly held a special meeting to honor the former South African president on his 95th birthday.
International diplomats and others joined at the United Nations to mark Nelson Mandela's 95th birthday and commemorate what the General Assembly declared Nelson Mandela International Day.
Former U.S. President Bill Clinton, the keynote speaker at the ceremony, said Mandela, since retiring as president of South Africa 12 years ago, has proved that you don't have to be in public office to serve the public.
"That is what this day is all about, that is what the Mandela Center is all about. And though he is old and frail and fighting for his life, what is in his heart still glows in his smile and lights up the room through his eyes. None of us has to be in public office to be of public service," he said.
Clinton said that was one of three lessons taught by Nelson Mandela's 95 years.
"First we must free ourselves, then we must free and empower others. Then we must serve as a way of life, not as a route to office. Those are the lessons that every person on Earth can learn, embrace and live by," said the former president.
Nelson Mandela's grandson Zondwa Mandela gives out food parcels as they celebrate Mandela Day with 67 minutes of public service to honour the 67 years Mandela served humanity by first fighting against white-minority rule and then consolidating racial harmony when he was president, at the SOS children's home in Mamelodi township outside Pretoria July 18, 2013.
Nelson Mandela's granddaughter Ndileka (R) serves soup as she celebrates Mandela Day with 67 minutes of public service to honour the 67 years Mandela served humanity by first fighting against white-minority rule and then consolidating racial harmony when he was president, at the SOS children's home in Mamelodi township outside Pretoria July 18, 2013.
Children hold placards as they gather to wish Nelson Mandela happy birthday at a township school in Atteridgeville, near Pretoria, July 18, 2013.
A portrait of Mandela is displayed on the windows of a building on his 95th birthday, Cape Town, South Africa, July 18, 2013.
A group of kindergarten children sing Happy Birthday outside the Mediclinic Heart Hospital where the former South African President is being treated in Pretoria, South Africa July 18, 2013.
A child sings as he and others celebrate Nelson Mandela's 95th birthday in Cape Town, July 18, 2013.
A banner of photos of Nelson Mandela set up outside the Mediclinic Heart Hospital in South Africa, July 18, 2013.
School children sing happy birthday to Mandela in front of his home in Houghton, Johannesburg, July 18, 2013.
A man prays as well-wishers gather to wish Mandela happy birthday outside Mediclinic Heart Hospital, July 18, 2013.
Members of the ruling party youth league sing outside the Mediclinic Heart Hospital where Nelson Mandela is being treated, July 17, 2013.
A man places a candle inside the St. George's Cathedral in Cape Town, South Africa, July 17, 2013.
A visitor takes a photo of a poster at the opening of an international exhibition of 95 posters celebrating the 95 years of the life of Nelson Mandela, at the University of Pretoria, South Africa, July 17, 2013.
U.N. Secretary-General Ban Ki-moon described Nelson Mandela as a towering figure in the worldwide fight for equality and justice, a model of compassion and integrity, a man who took on and then gracefully relinquished the responsibility of power.
"Nelson Mandela is a giant of our times. He gave 67 years of his life to the struggle for human rights. On this international day, the United Nations and the Mandela Foundation are calling on people around the world to devote at least 67 minutes of their time today to community service," he said.
Mandela is revered for his role in bringing down South Africa's discriminatory apartheid government. He spent 27 years in prison -- then emerged to become South Africa's first black president while steering the country toward peace and reconciliation.
Andrew Mlageni, 87, who was imprisoned with Mandela during the apartheid era, also spoke of the commitment to service shown by the man he referred to as Madiba -- Mandela's clan name.
"Madiba has become the symbol of hope for mankind because his essence was and remains for the restoration of dignity and shared humanity. For many in the world, he represents the desire for a world free from want, marginalization and fear," he said.
The American civil rights leader Jesse Jackson told the General Assembly that people should remember that before Nelson Mandela was a president, he was a freedom fighter.
"Mr. Mandela is our living response to all the cynics who seek to convince us that the world will forever be as it is now. Because of Madiba, standing on his shoulders we are a bit taller, sharing his vision we see a bit further, because of his sacrifice, we work more diligently, we are made better. He is a giant among men," he said.
He also said Mandela is a constant reminder that - as Jackson put it - truth crushed down to earth will invariably rise again.