The man accused of faking sign interpretation next to world leaders at Nelson Mandela's memorial says he has schizophrenia and had visions of angels coming into the stadium.
Thamsanqa Jantjie said he was trying not to panic because there were "armed policemen around me." He also said he has been violent in the past.
Mr Jantjie, who stood gesticulating three feet from US President Barack Obama and others who spoke at the ceremony that was broadcast around the world, insists he was correctly doing proper sign-language interpretation for the deaf.
In a series of interviews, he also apologised for his performance that has been condemned by sign-language experts who said he had been merely signing gibberish.
Thamsanqa Jantjie did describe his qualifications for being a sign language interpreter, but said he works for an interpreting company that paid him $85 for interpreting Tuesday's event.
Mr Jantjie did not address allegations by sign language experts that he faked interpretation for the memorial attended by scores of world leaders and broadcast internationally.
The Star newspaper quoted him as saying: "I tried to control myself and not show the world what was going on. I am very sorry, it's the situation I found myself in."
He added that he was once treated in a mental health facility for more than a year.
His statements raise serious security issues for Mr Obama, other heads of state and UN Secretary-General Ban Ki-moon who made speeches at FNB Stadium in Soweto, Johannesburg's black township.
"What happened that day, I see angels come to the stadium ... I start realising that the problem is here. And the problem, I don't know the attack of this problem, how will it come. Sometimes I get violent on that place. Sometimes I will see things chasing me," Mr Jantjie said.
"I was in a very difficult position," he added. "And remember those people, the president and everyone, they were armed, there was armed police around me. If I start panicking I'll start being a problem. I have to deal with this in a manner so that I mustn't embarrass my country."
Asked how often he had become violent, he said "a lot" while declining to provide details.