Cliff looked relaxed when the court adjourned and was seen smiling regularly throughout proceedings.
Mpofu said that M-Net did not have any valid grounds for dismissing Cliff.
He said that Cliff has become subject to racist allegations after M-Net published a statement following his tweet
"M-Net claims the problem is the way Cliff is perceived in the public eye," Mpofu told the court.
"His only offence is sending the tweet that people don't understand freedom of expression."
Wim Trengove, representing M-Net, said the former Idols judge did not have any contract with M-Net as emails did not count as an oral agreement.
"An oral agreement is made to parties who speak to one another in person, not via email," he said.
"To say there was oral agreement is simply a fabrication."
Trengove argued that M-Net had a right to decide who they associated themselves with.
"Idols judges are employed to delight and entertain, not to shock and offend," he told the court.
"M-Net only proposed an offer for the 2016 season. Cliff never responded to the offer."
M-Net had an absolute discretion to terminate his contract on a week's notice and Cliff was not entitled to anything.
Trengove said Cliff had the right to say whatever he wanted, but he did not have the right to be an Idols SA judge.
M-Net does not want to be associated with a person who is largely perceived to be a racist, Trengove said.
"What M-Net is saying, is that your view and conduct has received response from a large constituency that you are a poster boy for racism."
Cliff is the cause of the harm to his own reputation and not M-Net the court was told.
"He (Cliff) destroyed his own reputation. His own conduct led to his damaged reputation and one cannot expect M-Net to be left with the burden of its repair."
Mpofu hit back by saying that freedom of expression is nothing but the right to offend.
He stated that public opinion does not give you the right to fire someone.
According to Mpofu the matter might as well be unopposed because M-Net had no valid arguments.
He referred to a statement made by Trengove about "our history" that has to be defended whereby Mpofu asked how someone who worked for Naspers could be in any position to make such a statement.
He said that Naspers was known as a company marketing the National Party during the apartheid-regime and therefore were just as guilty of playing a role in the genocide of apartheid.
"If I dare say it, Cliff was discriminated against because he is white," Mpofu told the court.
Judge Caroline Nicholls said she would deliver judgment before 10:00 on Friday.