An agreement with the family, that Goldstone would not be in attendance at the synagogue service, was reached after negotiations between the SAZF and the Sandton Shul, where the event is due to take place.
Avrom Krengel, chairman of the SAZF, who was reportedly not keen to reveal much, said: “We understand there’s a barmitzvah boy involved - we’re very sensitive to the issues; at this stage there’s nothing further to say.”
While Krengel said the SAZF had interacted on the matter with the chief rabbi and others, his organisation was “coming across most forcefully because we represent Israel”.
Goldstone was reluctant to reveal further details, and is reported to have said: "In the interests of my grandson, I’ve decided not to attend the ceremony at the synagogue."
A bar mitzvah is a coming of age event for a young Jewish boy, when he symbollically becomes a man.
"There is a belief amongst right-wing Zionist organisations that defaming and humiliating Jewish critics of Israeli policy, will set an example that would intimidate others into silence," Isaacs, co-ordinator of a community-based education NGO, said.
Isaacs led a Jewish youth movement that campaigned for a just resolution of the Palestinian-Israeli conflict.
'A lot of anger'
Moshe Kurtstag, Rabbi and head of South Africa's Jewish religious court, said that he believed Goldstone had done a tremendous disservice not only to Israel but to the Jewish world.
"I know that there was a very strong feeling in the shul, a lot of anger."
Arthur Chaskalson, retired president of the constitutional court, said it was "disgraceful" to put pressure on a grandfather not to attend his grandson’s bar mitzvah.
"If this has the blessing of the leadership of the Jewish community in South Africa, it reflects on them rather than Judge Goldstone. They should hang their heads in shame."
David Saks, associate director of the South African Jewish Board of Deputies told Al Jazeera that this was a SAZF issue and they were not prepared to make any statement.
"Israeli apologists in South Africa behave as they did under Apartheid when they failed to recognise the humanity of black people. They have no understanding of constitutional values or the humanity of Palestinians," Zackie Achmat, the renowned South African HIV/AIDS activist, said to Al Jazeera.
"The SAZF is not only ignorant of the Goldstone report but they have violated his rights to belief, family life and dignity."