In a video of the incident, Victor Mlotshwa was seen begging for his life as he was pushed into the coffin
Two white South African farmers have been jailed for more than a decade after forcing a black man into a coffin.
Willem Oosthuizen and Theo Jackson were found guilty of attempted murder and kidnap after they filmed themselves shoving Victor Mlotshwa into a coffin and threatening to kill him.
On Friday, a judge in Mpumalanga sentenced Jackson to 14 years and Oosthuizen to 11 years.
They had pleaded not guilty to an array of charges after a video showing them assaulting Mr Mlotshwa went viral in August 2016.
In the video, Mr Mlotshwa begs for his life as he is pushed into the coffin by the two white farmers.
One of the men pushes the lid of the coffin down while the other threatens to put petrol and a snake inside.
They claimed he had tried to steal cables from their farm and threatened to kill their families and burn farm crops.
Mr Mlotshwa was in court throughout the hearings, and was present at the sentencing.
He denied stealing cables and claimed the two farmers picked him up as he tried to take a short cut.
Judge Segopotje Mphahlele said: "The most appalling act of the accused was to put the complainant in a coffin against his will.
"Whilst in the coffin they threatened to set it alight. They asked him how he wanted to die - quickly or slowly.
"The conduct of the accused... goes against the spirit of the constitution."
Defence lawyers have said the sentences were too harsh.
Carel Taute, Jackson's lawyer, told Al Jazeera: "The whole case is strange. Even the fact that it was taken to the High Court, when there was no murder.
"I find it ironic that the judge said that the judgement had to build relations within the community. I am afraid this will do the opposite."
The case prompted national outrage and sparked a debate over the legacy of apartheid, which ended in South Africa in 1994.