Nofomela,who has applied for amnesty for a series of crimes he committed while working as a Vlakplaas undercover policeman during the early 1980s, is serving a life sentence for the murder of the farmer, named Lourens.
He was originally sentenced to death for the murder, but hours before going to the gallows he made revelations about his activities as a police hitman and was granted a stay of execution.
Nofomela told the hearing he had gone to Brits with the intention of stealing from Lourens, who was believed to have a large amount of money. Lourens had called him a kaffir and threatened him with a firearm.
"This made me angry because while at Vlakplaas I worked with whites who were oppressing blacks... I was helping whites in their battle against the ANC," Nofomela.
He began wrestling with Lourens and drew a knife and stabbed him.
He was later told to deny everything by his commander at Vlakplaas, Eugene de Kock, who said the matter would be taken care of.
It was put to Nofomela by one of the committee members, Judge Andrew Wilson, that he killed Lourens in order to take his money and not because he felt insulted.
Nofomela replied that he still felt deeply affronted when referred to as a kaffir.
The hearing continues.