Distressed, I ran home to my father. "Why," I asked, "would anyone want to spit on Shylock's Jewish gaberdine?"
"They call it anti-Semitism," he said. "You will experience it at various times throughout your life. Learn to rise above it."
Boloney, I thought. Unadulterated rubbish. Not here. Not now. Not in Britain. From my childish perspective anti-Semitism belonged to the swastikas and yellow stars of my grandparents' world.
Eight years later, when I felt the icy gush of the water poured over me by a fellow student in the university canteen, when I heard him yell "you mean Jewish bitch," because I wouldn't get up and buy him a coffee, my father's words reverberated.
But that was 10 years ago. That was before Britain opened its apparently unprejudiced arms to the celebration of all cultures. Today, if I say so myself, it has become almost hip to be Jewish.
"It's Woody Allen, it's bagels, it's salt beef, it's Soviet Jewry, it's comedy," says Matthew Kalman, editor of New Moon, the trendy Jewish monthly for twenty-, thirty-, fortysomething Jews.
Anglo-Jewry is experiencing two diametrically opposed trends - one towards greater orthodoxy and observance, the other towards a secular Jewish culture that has little to do with religion and everything to do with film, food and comedy. We may eat bacon, grace the inside of a synagogue no more than once a year and choose non-Jewish partners, but at the same time we can still feel very culturally Jewish.
British Jewish comedians are part of that culture and have taken their lead from the US Jewish comic Jackie Mason. Once a rabbi, he left the pulpit for the stage and now makes millions with his irreverent Jewish humour. In Britain, Peter Moss, Dave Schneider and Ivor Dembina are getting up there and laughing at their own Jewish neuroses, their Jewish mothers and their predilection for chicken soup and chopped liver. Ten years ago, they might just have dared to sneak one Jewish joke into their repertoire.
The Yiddish language has begun to penetrate British culture. Chutzpah and schlep, schmooze and schmock are no longer just the preserve of the Jews. If, as George Steiner once said, being a Jew is being a member of a club, the doors to that club, or at least to its secular division, are now firmly ajar.
Since the massacre of the Jews in York in 1190, anti-Semitism has been present in British society in one form or another, but with these significant cultural changes and the attendant increased understanding between Jew and Gentile, one would expect a decrease in social anti-Semitism. Mike Whine, of the Jewish Board of Deputies, believes this is so. "I think social anti-Semitism in Britain is on the decline. Or at least the number of reported incidents are on the decline." My brother, for example, never reported a recent incident in the West End cafe he used to go to before work.
The owners found out he was Jewish and began to call him Moshe. He took it as a bit of fun. But one day he left a banana skin on the table. The proprietor of the restaurant turned to her son and said: "Hitler should have killed him with the rest of them."
I advised my brother to drink his cappuccino elsewhere and I mentioned his nasty experience to a couple of Jewish friends. One of them, who works in a large international investment bank, said: "Nowhere in the world have I experienced such awful anti-Semitic comment as in the City. A few weeks ago I was on a company outing. Someone made a Holocaust joke about there being 11 holes in gas chambers, so that the Jews could block 10 with their fingers and the 11th would let in the gas. I couldn't believe my ears, so I asked him to repeat it. He did and I told him it was offensive. He said: 'What's the problem? There are no Jews here.' I told him I was a Jew and he came up with that wonderful line 'some of my best friends are Jewish'."
Stories of City anti-Semitism abound, even among those in their twenties and thirties, and more often than not they are Holocaust-related. The same friend said: "We were looking at the names on a list of mortgages. There were a couple of Goldbergs and a Levy. A colleague of mine said: 'Looks like Hitler didn't quite finish off his job'."
Whether or not the comments emanate from hatred or ignorance is almost irrelevant. They have the same effect.
Two weeks ago the British Jewish community was up in arms about a remark made by the world-renowned Royal Free Hospital breast cancer specialist, Santilal Parbhoo. He had told one of his patients she needed to lose weight. She said she would find it difficult. He replied, "They managed it in Auschwitz." Mr Parbhoo knew she had lost most of her family in Bergen Belsen. When he learned that the woman was deeply distressed by his comments, he refused to retract them and said they had been entirely appropriate.
His astounding insensitivity was, in my view, tantamount to anti-Semitism. Holocaust comments and Holocaust jokes are definitely a no-no. But often anti-Semitism is much more subtle and much more covert.
A Jewish radio producer in her twenties says, "It's not what they say, it's the way they say it. It's all in the looks and the tone. Every time a Jewish story comes up, I am made to feel like 'Jew' is a dirty word, as if the whole of the Jewish world is distasteful and populated with people like Maxwell."
Part of the problem is that however hard she tries, however well she does professionally, she will never entirely slot into the British class system.
The days when Disraeli had to renounce his Judaism to become prime minister may be gone, but vestiges of entrenched anti-Semitism remain in the Establishment. A few years ago, when Margaret Thatcher had appointed several Jews to her cabinet, including Leon Brittan and Nigel Lawson, a Tory MP was overheard saying there should be more "red-blooded Englishmen in Parliament". It was understood that he meant there should be fewer Jews.
The French philosopher Jean- Paul Sartre said: "C'est le regard de l'autre qui definit le Juif" - "A Jew is defined by the way a non-Jew treats him" - and at times fear of that treatment pushes the Jew to lose pride in his or her own identity. Last year at a cocktail party I met an aspiring young diplomat. I recognised her from somewhere. I knew she was Jewish and I made some comment on the subject. She turned a whiter shade of pale and said: "Please don't divulge that piece of information here. It would do my career no good at all."
But are we sometimes just a little too quick to think the non-Jew is persecuting us? A Jewish person told me the story of Mr Cohen and Mr Levy working on a property deal together. Mr Cohen phones Mr Levy and he says, "I have good news and bad news. The good news is I've bargained them down to pounds 5m on the building. The bad news is they want a pounds 25 cash deposit."
I found the joke funny when I heard it from a Jew. When a non-Jew told it to me some months later, I felt myself go cold at the prospect of his stereotyping the Jew as mean. The joke-teller may indeed have been prejudiced and a nasty anti-Semite. On the other hand he may just have been telling an amusing tale with absolutely no sinister sub-text. The problem is, I don't know where he's coming from. Herein lies a crucial point.
The British may like to think of themselves as paragons of political correctness, yet jokes about the Italians, the Irish, the Blacks and the Jews are still very much out there. And they are not always designed to hurt. But centuries of persecution have programmed us to almost always assume the worst. It's the syndrome of the one-armed Jewish violinist who thinks the London Symphony Orchestra won't accept him because it's anti-Semitic. It's Woody Allen's story of the guy at the bus stop who asks him, "when's the bus due?" Paranoid, Allen hears "due" as "Jew" and says: "You see, it's everywhere."
To accept occasional blame for over-sensitivity is not to suggest that anti-Semitism in Britain is illusory. It rears its ugly head in politics, in the City, in the media, and in the legal profession.
It takes the form of underhand comment and horrific Holocaust jokes, but it can be more sinister. Last Thursday anti-Semitic insults were daubed on a North London synagogue wall in huge silver and gold letters. There are revisionist historians such as David Irving and Lady Birdwood who suggest that the Jews have blown the Holocaust out of all proportion, and there is Combat 18, the Fascist group that wants a "Jew-free world".
But it is social anti-Semitism that is most likely to threaten the comfort of our daily lives. The findings of a survey published in last year's Antisemitism World Report showed that 12 per cent of Brits would rather not have a Jew as a neighbour.
So should we be pleased that 88 per cent don't mind if there's a Jew next door?
Far be it from me to ignore the fact that the likes of Woody Allen have brought the British Gentile closer to an understanding of Jewish culture and that at least on one level the divide between Jew and Gentile has narrowed. Far be it from me to exaggerate social anti-Semitism in this country. I wouldn't want to offend the sensibilities of the non-Jew, any more than I would wish him to offend mine. After all, some of my best friends are Gentiles.