​​The documentary Black Christmas tells the painful but poignant story of how one of the perpetrators of the 1996 Christmas Eve bombing in Worcester found redemption and forgiveness in the same community he had once hated and struck at. The first public screening of the film, held at the Labia Theatre on Thursday, 14 April 2016, kicked off an equally powerful discussion on the place of forgiveness in post-apartheid South Africa.

On Christmas Eve in 1996, the then 17-year-old Stefaans Coetzee and three other members of the Afrikaner Weerstandsbeweging (AWB) detonated a bomb in the packed Shoprite shopping centre in Worcester.

A woman and three children died in the explosion. Some 67 other people were injured. The Worcester Bombers, as they became known, were all sentenced to life in prison.

For a long time after his incarceration, Coetzee clung to the 'Israel Vision' of the AWB that Afrikaners were the chosen people of God, a conviction he had picked up at the feet of the man he – legally an orphan – had become to view as his father. But at the same time he was tortured by the thoughts of, especially, the young the lives he had taken. His road to redemption started in 2006 through an unlikely source – 'Prime Evil', aka Eugene de Kock, the former commander of the notorious Vlakplaas unit of the Apartheid-era police and Coetzee's fellow inmate in Pretoria Central Correctional Centre. De Kock encouraged Coetzee to take pride in being an Afrikaner, but urged him to renounce his affiliation to the AWB.

By 2009, Coetzee started to meet some of the survivors of the 1996 attack, including Olga Macingwane, still limping from her injuries suffered in the bombing. Four years later he would meet 60 survivors and families of victims in a meeting at the Pretoria prison. In those tearful encounters, some – as Macingwane had done in their 2009 meeting – told him that they had forgiven him. Others said they never would.

In 2015, Coetzee was granted parole after the likes of Macingwane and community leader Harris Sebiko had spoken on his behalf.

Coetzee's story is told in Black Christmas, a new documentary directed by filmmaker Mark J Kaplan and produced by Stellenbosch University's (SU) Professor Pumla Gobodo-Madikizela. Gobodo-Madikizela's acclaimed 2003 book, A Human Being Died That Night: A South African story of forgiveness, also dealt with the issue of forgiveness, structured around her many interviews with De Kock.

The film also tells how Macingwane and others had chosen to forgive Coetzee, and how Worcester had sought to bridge the divide between the town's communities through initiatives like its Hope and Reconciliation Process and annual Peace Table, supported and guided by Dr Deon Snyman of the Restitution Foundation.

At a packed screening of the documentary at the Labia Theatre on Thursday, 14 April 2016, Kaplan and a panel of speakers explored the lessons to be learnt from Coetzee's and the Worcester community's story. This first public screening of the film was hosted by Stellenbosch University, the South African office of the Konrad Adenauer Stiftung, the Restitution Foundation (a small faith-led, Cape Town-based NGO), and the Institute for Justice and Reconciliation (IJR).

"The film really straddles different fault lines in this country," said Kaplan in introducing the documentary. It deals with painful subjects, some caused by systemic problems in South Africa, he added. "In spite of these things, I think the film has surprising answers, and is ultimately uplifting."

Following the screening, the three panellists  – Professor Steven Robins of the Department of Social Anthropology at SU; Mondli Makhanya, editor-in-chief at City Press; and writer and activist Sisonke Msimang – talked of the lessons offered by the film. Robins spoke of the damage done by Coetzee's family life, the generosity shown by the victims of the attack, and how forgiveness probably best comes through interventions other than structured state programmes. "But the question I want to ask is, can you have a programme of forgiveness?"

The film served as a painful reminder of what had not yet been done in South Africa, added Makhanya. "It tells us what we had not gone through as a nation," he said. "This process that the people in Worcester had gone through – they went through what South Africa should have gone through from 1994 to today."

Msimang talked of empathy, of the resilience shown by the victims (some who had to go back to work at Shoprite just days after the attack), and the other stories that could also be told – of the victims who had not forgiven, of the perpetrators who had remained unapologetic. "There is a national story of structural power, and the talking and the sorry, versus the doing and the building," she said. "That for me is the real question – the extent to which we can link forgiveness to more than a sorry at a national level, to a doing."

Some of that is being done in Worcester, explained Sebiko, who along with other community members had travelled to Cape Town for the screening. Desperate to make amends to the people he had so injured, Coetzee – now living in Pretoria – is involved in a project that would help community members set up a sizeable hydroponic garden on a piece of land donated to them, Sebiko recounted. It's Coetzee's way of giving back to the town, he said.

"Stefaans wants to do something for the people of Worcester."

• From left: Professor Steven Robins of the Department of Social Anthropology at SU; Mondli Makhanya, editor-in-chief at City Press; and writer and activist Sisonke Msimang; and facilitator, Prof Pumla Gobodo-Madikizela of Stellenbosch University in the panel discussion at the screening.