Machel, who is a former first lady of both South Africa and Mozambique, encouraged acceptance of all nationalities.
Nelson Mandela's widow, Graca Machel has appealed for African unity at a memorial service for Manuel Jossias, who was hitherto refereed to as Emmanuel Sithole, the Mozambican whose stabbing to death in the recent xenophobic attacks in South Africa was captured in pictures.
In an emotional speech in Johannesburg, Machel called Mozambican Manuel Jossias' murder "a symbol of what must not happen again", adding that the recent violence should be "a wake-up" call for the entire region.
Machel, who is a former first lady of both South Africa and Mozambique, encouraged acceptance of all nationalities:
"I am South African. I am Mozambican. I am Zambian. I am Zimbabwean, migration is in our blood! The borders were created by colonisers. They mean nothing to us because we are one."
She also described the recent violence as an "expression of self-hate which was inculcated by the system of apartheid" and stressed that similar attacks would happen again unless countries throughout the region were able to provide better economic opportunities for their people.
BBC reports that after her speech, the former first lady broke down in tears.
Machel was married to Samora Machel, the first president of independent Mozambique, who died in a 1986 plane crash and in 1998, on his 80th birthday, she married Nelson Mandela.
Speaking on behalf of the family, Jossias' cousin Veronica Sithole told the congregation that he had been the breadwinner for the whole family.
She married Mandela on his 80th birthday, in 1998.
Meanwhile, 4 suspects appeared in court last week over Mr Jossias' killing. The case has been adjourned until 4 May.