Mr Halasz was born in Budapest a month after the start of World War II, but would survive and make it to Australia, going on to found swimwear giant Seafolly with his wife and fellow Jewish refugee Yvonne Halasz.
He recounted his harrowing first years of life, during a highly-anticipated public hearing by the Royal Commission on Anti-Semitism and Social Cohesion on Monday, sparked by the Bondi Beach terror attack on December 14.
"What is happening in Australia today is not a faint echo of a distant past," Mr Halasz said.
Forced into hiding during the Nazi occupation of Hungary, Mr Halasz's mother risked everything on December 15, 1944, when she went to visit her father for his birthday at a separate apartment hideout.
''She kissed me goodbye and that was the last time I saw her. I was five years old," Mr Halasz said.
While Mr Halasz's mother was visiting her parents, the Hungarian Nazis raided the building, took all the Jews down to the banks of the Danube River and shot them.
Growing up in an environment where being Jewish was something to be hidden, Mr Halasz said coming to Australia was the first time he felt comfortable being openly Jewish.
But he was not prepared for the way in which the country changed after the October 7 attacks, with Jewish businesses and schools targeted and the community feeling under threat.
"I found myself, for the first time since childhood, afraid to wear my Star of David in public," he said.
"I found myself for the first time since I fled Hungary feeling that my identity was something I should hide."
Mr Halasz was far from alone in feeling afraid of the future should anti-Semitism continue.
High-profile Jewish advocate Alex Ryvchin said seeing his former Sydney home firebombed in early 2025 felt like an attack on the entire Jewish community.
"I've had families calling me and saying completely calmly, 'will you tell me when the time to go is?" he told the inquiry.
Chief Minister of Sydney's Great Synagogue, Rabbi Benjamin Elton, told the hearing members of his congregation had been physically assaulted and he and his staff had been threatened and abused for being Jewish.
Mount Sinai College board president Stefanie Schwartz told the inquiry in Sydney her five-year-old daughter was at Bondi on the day of the attack and remains highly traumatised.
The school in Maroubra, in eastern Sydney, was targeted with graffiti branding Jews as ''terrorists'' and ''dogs'' in January 2025.
''It was clear that the intent was to intimidate children,'' Ms Schwartz said.
A nearby day care centre was destroyed in an arson attack Ms Schwartz said she believed was mistargeted and intended for her school.
The first witness to give public evidence at the inquiry was daughter of one of the Bondi terror attack victims, Sheina Gutnick, who recounted being abused for being Jewish while in a shopping centre with her baby.
Ms Gutnick's 62-year-old father Reuven Morrison was killed during the attack in Bondi after hurling a brick at one of the gunmen involved.
Ms Gutnick said in December 2024 - a year before the deadliest shooting since the Port Arthur massacre - she was walking through Westfield Bondi Junction with her baby when a man pointed at her Star of David necklace and called her a ''f***ing terrorist''.
The commission's initial hearing block will run until May 15.