Jewishness is achieved by descent through the mother’s line, or by conversion. But within Judaism, as within Christianity, there are different groupings, with some regarded as more or less “Orthodox” than others. In this case, the child’s father was Jewish by birth but his former wife was not. She converted but with a Progressive synagogue, meaning that she would never be recognised as Jewish by the Office of the Chief Rabbi, who heads Orthodox Jewry.

If her own mother had been Orthodox, it would not have mattered if she herself had never attended synagogue in her life, ate pork every day and worked like a slave on the Sabbath. It would not have mattered if she declared herself an atheist. Her ethnic descent through her mother would still have allowed her child a coveted place at JFS. But no matter how religious she or her child became after her conversion, that lack of ethnic identity meant that without a conversion certificate approved by the Chief Rabbi’s Beth Din, in their eyes neither she nor her child was Jewish.

Faith schools are allowed legally to discriminate on religious grounds but not racial grounds. The United Synagogue has already spent more than £150,000 on the case, the JFS has also spent considerable sums, and they will be seeking financial help from the community as they continue their fight to the Lords.

As Lord Justice Sedley says in the judgment, one of the evils that successive Race Relations Acts have been directed against is anti-Semitism. “None of the parties to these proceedings wants or can afford to put up a case which would result in discrimination against Jews not being discrimination on racial grounds,” he writes.

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