Jeremy Corbyn’s office asked us whether it would be insensitive to release a statement on Friday afternoon, before the Jewish Sabbath. We said it would be an act of tremendous bad faith. He clearly ignored us.

He deliberately picked a time that he knew all the mainstream Jewish organisations were closed for our holy day. This tells you as much as you need to know about him and the contempt with which many of those around him regard the Jewish community.

As the latest series of scandals broke, we waited over a week to hear from Jeremy Corbyn. When he chose to speak, much of what he said was a tired re-hash of things that had been said before, and neither his article nor his video message on Sunday did much to move us forward.

Despite almost every reputable institution – and much of his own institution – being ranged against Labour’s watered-down antisemitism code, his op-ed defended it. The only problem, he seemed to say, was that Labour did not consult the Jewish community.

Labour did not consult the Jewish community over their definition of antisemitism – the very thing that we experience. But they did know what we thought. The Board of Deputies, the Jewish Leadership Council, the Community Security Trust, the Chief Rabbi and 68 rabbis from across every denomination told him we objected to their proposed weaker code.

Labour's national executive committee was even subjected to an odious diatribe about Jews in general, and rabbis in particular, by one of its members, Peter Willsman. Jeremy Corbyn himself sat through that diatribe and did nothing. The General Secretary Jennie Formby then let Peter Willsman off scot-free.

While they seem to give bigots a free pass, Labour subjects anti-racist MPs like Margaret Hodge and Ian Austin to ‘show trial’ disciplinary procedures, without even telling them the exact charges against them, but apparently for daring to criticise Corbyn and Labour’s record on antisemitism.

In the almost 1,300 words of his article, and further words in his subsequent video, Corbyn was totally silent on the fact that he himself supported a motion seeking to remove the word ‘Holocaust’ from Holocaust Memorial Day; on his describing a Hamas terrorist whose bomb murdered Israelis in a restaurant as ‘brother’; or about the conspiracy theories about how Israel was behind Islamist terrorism in Egypt that he shared on the Iranian régime’s Press TV.

Until Corbyn can honestly and fully own up to the problematic nature of some of his own past actions, he will struggle to lead the cultural change that is needed to clear the decks of a loud minority within Labour who behave in this way.

In this article, he makes the claim that “disciplinary cases are being dealt with much faster”, but this in itself is an admission that Labour has failed to meet even its low bar of resolving all the high-profile cases and almost all of the outstanding cases by the end of July. It is now August.

Let us be clear, it is not words, but only actions that have ever mattered. If Jeremy Corbyn does not want this to be the summer in which his credibility as an anti-racist dies, he must ensure that the following happens urgently:

· Labour needs to accept the International Holocaust Remembrance Alliance definition with all its examples. It cannot just decide that some forms of antisemitism are permissible to Labour members.

· Proper action should be taken against Mr Willsman and Corbyn should call for all charges against Margaret Hodge and Ian Austin to be dropped.

· Labour needs to open its opaque and politicised disciplinary process to independent scrutiny as it has repeatedly proven that it cannot be trusted to dispense anything like justice, in anything approaching an appropriate timescale.

· Corbyn needs to own up to and apologise for the problematic nature of his own past actions.

More than 100 days after our organisations met Corbyn, we sadly seem to have gone backwards rather than forwards. The question of whether Corbyn is willing or able to lead the cultural change necessary to banish antisemitism from the Labour Party has never been more important. At the moment, a continuing refusal to do what is necessary just proves how badly Jeremy Corbyn is failing to tackle the world’s longest hate. He should remember that inaction in the face of racism is complicity.

Marie van der Zyl is President of the ​Board of Deputies of British Jews. Jonathan Goldstein is Chair of the Jewish Leadership Council.