Judgment has been reserved in the Equality Court case between the South African Human Rights Commission (SAHRC) and Velaphi Khumalo over racial slurs made on Facebook.
Judge Roland Sutherland, sitting in the South Gauteng High Court in Johannesburg, heard arguments from the parties and said he would assess the evidence before giving judgment.
Khumalo's representative, Stuart Wilson, argued that a practical, common-sense approach was required in the case.
He said the SAHRC was coming after Khumalo for substantially the same words for which the ANC successfully sued him.
"What the SAHRC wants is to punish Mr Khumalo twice for the substantially the same conduct," Wilson submitted.
Khumalo posted his comment on Facebook in January 2016, after an incident in which former estate agent Penny Sparrow referred to black people as monkeys in a complaint about litter on the beach.
He wrote: "I want to cleans this country of all white people. we must act as Hitler did to the Jews. I don't believe any more that the is a large number of not so racist whit people. I'm starting to be sceptical even of those within our Movement the ANC. I will from today unfriend all white people I have as friends from today u must be put under the same blanket as any other racist white because secretly u all are a bunch of racist fuck heads. as we have already seen (sic)."