Jeremy Corbyn said anti-Semitism has "no place whatsoever in a civilised society" when confronted by an audience member after his speech at the CBI conference today.
An audience member asked what he will do to make sure Labour is not the "party of the many, but not the Jew".
The Labour leader replied saying he has opposed racism all his life and was brought up to be anti-racist.
Mr Corbyn said: "I've spent my life opposing racism in any form. Be it done by the far-right or by the random attacks on individuals, or against a man that was murdered outside my house because he happened to be a Muslim and there happened to be a racist person driving a vehicle that thought it was OK to drive in a crowd of worshippers.
"Just as much as those people that attack synagogues, daub fascist graffiti over them, or attack Jewish people in this country, the USA or anywhere else, have no place whatsoever in a civilised society."
He added: "The history of the Jewish people has been one of the most unbelievable and egregious - (with) attacks on them in central Europe throughout the early part of the 20th century, which of course ended with the Holocaust and all the horrors that went with that.
"That is where racism leads you to if you don't challenge it in the first place.
"But it's also about ensuring that every young person in our society is guaranteed a place of safety free from oppression and free from racism in any form."
During his speech at the CBI conference, Corbyn said Labour's plans would tackle inequality and address climate change.
He said: "What a Labour government will do is raise the platform on which our whole society stands so that businesses and individuals can build themselves up even higher and reach their dreams.
"You know despite people’s differences, there are things we can all agree on. None of us wants to live in a society where we have to step over rough sleepers on our way to work.
"None of us wants to live in a society where foodbank collection points are needed in every supermarket. None of us wants to live in a society where one in three children grows up in poverty.
"I just want to live in a decent society. And I know you do too. It doesn’t have to be an either/or choice because the opportunities created for businesses under a Labour government will be immense."
Corbyn also said a four-day week will be see productivity increase and said everyone would support a fairer and more egalitarian society.
He also unveiled plans to give all local authorities the right to take bus services into public ownership if Labour wins the General Election.
Corbyn said it is "nonsense" to call him anti-business and made the pitch that Labour is the party to deliver the investment and Brexit deal that bosses desire.
He told the organisation's annual conference in London that he plans to give councils the power to undo some of Margaret Thatcher's privatisation of the bus network in the 1980s.
Mr Corbyn said Labour will be "empowering local authorities to develop bus services where they don't exist" by extending powers to bring routes into public ownership or franchise "to all".
So far, only metro mayors have the power to re-regulate buses under the Bus Services Act 2017.
While Labour's official manifesto launch is not until Thursday, it is understood that bus pledges could also include a policy to fund free bus travel for all under-25s.
Mr Corbyn's speech was in stark contrast to the previous speaker - Prime Minister Boris Johnson - who pledged to postpone further corporation tax cuts in a bid to divert £6 billion to the "priorities of the British people".
