Neville Lawrence says has forgiven his sons killers, 25 years after the murder that shocked Britain.
Stephen Lawrence was 18 when he was murdered by a gang of racists in Eltham, south-east London in 1993.
Only two of the group of up to six who attacked the teenager and his friend Duwayne Brooks, simply because they were black, have been convicted of murder, but the rest have evaded justice.
Neville Lawrence, 76, said the decision to forgive them was the hardest he has ever made, and that he struggles to put into words the devastation caused to his family when his son was killed.
His father said: The fact that I had to lose my first child has been devastating.
He said the decision to forgive Stephens killers will be the hardest I will ever make in my lifetime, but that he is embracing Christian faith. He plans to spend the 25th anniversary of his sons death in church.
David Norris and Gary Dobson are both serving life sentences, while three other men who have consistently been accused of the killing but never convicted are Jamie Acourt, 41, from Bexley; his brother Neil Acourt, 42, who uses his mothers maiden name Stuart, and Luke Knight, 41, both from Eltham.
The initial investigation into Stephens death was hampered by incompetence, racism and alleged corruption.
A key moment was when Mr Lawrence and his ex-wife Doreen met Nelson Mandela two weeks after Stephen died.
When I met him for the first time I was so inspired by his persona and the way he talked to people, Mr Lawrence said.
He made it clear to us that in his country it was something that they go through every day, but never in his wildest dreams did he think that something like that would happen in a place like Britain.
Meeting him gave me the courage to do some of the things I have done over the years.
Other families came to my rescue as well. When you are going to go on a journey, if somebody else who has been through it comes and talks to you they can give you an idea what youre going to face down the road.
Mr Lawrence, who speaks to young people to spell out the dire consequences of carrying a weapon, said: Right now with the violence, and the knife crime violence, it is even more urgent now that I talk to these youngsters and explain to them the pain and the suffering they inflict on families.
Mr Lawrence and his former wife, who is now Baroness Lawrence, have campaigned for more than two decades to get justice for their son.
The botched case led to a major public inquiry and eventually a change in the law to allow Dobson to be tried twice for murder.
Detectives have admitted their investigation is unlikely to progress without new information.
Former plasterer and decorator Mr Lawrence believes that in death his aspiring architect son has become a legend.
He said: When these boys killed my son Stephen, they created a legend. In his death, Stephen is a legend.
There is debate about racism, there are organisations set up to help to make people understand about racism, the police have been put under the spotlight because of Stephens death.
The father-of-three and his family, who have fought with immense dignity despite scandalously poor treatment by the police, will never escape the pain of what happened.
He said: Maybe sometimes people think you can just brush things aside. You can never brush this aside, this is going to live with you for the rest of your life.
This is a life sentence that you cant finish. The only time my life sentence will be finished is when Im in the ground.