His name was Shmuel Ha-Nagid. He was a warrior. He was a vizier. He was a Jew. And when he rode into battle for Granada, his shochet trundled behind him with kosher meat. Now, a thousand years since, we should remember him — and the confidence with which this prince lived as both a talmudist, a politician and a poet — because in the twenty-first century, the approach to the Torah of this eleventh century commander of a Muslim army is foreign to mainstream Orthodoxy.

Shmuel Ha-Nagid’s approach was the Sephardic Torah — the Rabbinical approach born in the citadels of the golden age of Muslim Spain. The school of Rabbis like Maimonides and Yosef Caro who prized the rational and the practical as they interpreted Jewish law. Rabbis who never saw a contradiction between secular life — not even as a Sultan’s warrior vizier — and a life of study and devotion. Theirs was a worldly Torah: to the point Maimonides even objected to a paid Rabbinate.

Yet today, Orthodoxy has pushed the Sephardic Torah school to the margins. Dominating over Orthodox Judaism is a yeshiva system that is structurally, culturally and halachically Ashkenazi. This is true even in Israel despite precious exceptions like Kisse Rahamim in Bnei Brak. Even when Israeli yeshivot have Sephardi or Mizrahi inscribed over the entrance, even where their Rabbis have lovingly preserved the melodies and the minhag of lost Spain and Syria; the truth is that in practice, their approach to Torah, Talmud and Halakha has been wholly Ashkenazified. Despite nearly half of Israeli Jews identifying as Sephardi or Mizrahi the Halachic tradition of Maimonides is becoming more or less irrelevant.

The recent memoirs of Britain’s former Sephardi spiritual head Rabbi Abraham Levy — A Rocky Road — is an urgent “how to” manual for how Sephardim and Mizrahim can stand up for their traditions. Writing in 1970 after a visit to Israel the Rabbi asked in his searing pamphlet, A Question of Survival, whether the Sephardic Rabbinic outlook, committed as it always has been to leniency, moderation and synthesis would even survive. What Rabbi Levy did next should be an inspiration to all Sephardi Rabbis in Israel and the diaspora: he helped get British Sephardim back into the business of training their own Rabbis. Since 2006 the Montefiore Endowment has been training a new generation of homegrown modern Orthodox Rabbis for British Jews in the traditions of Maimonides. This is how you save your own halachah.

The pitiful sight that Rabbi Levy witnessed in Israel in 1970 of “passive” Sephardim and Mizrahim living mostly on the margins of an Ashkenazi society has been turned on its head when it comes to Israeli food and Israeli music, and to a certain extent Israeli politics. But less so when it comes to Rabbis. Instead to this day Israeli Sephardi and Mizrahi Rabbis continue to try and prove themselves by seeking to “out black” the Ashkenazim — and in so abandoning their own moderate traditions.

Israel urgently needs more moderate and genuinely Sephardi and Mizrahi yeshivot. Beyond Britain, so does the Diaspora: there are over 300,000 Sephardim in France and at least 400,000 Sephardim and Mizrahim in the USA. Yet with no drive to train new Rabbis, their religious outlook is at risk. As older Rabbis retire, their successors will inevitably be the products of the severe Ashkenazi system. And the influence of a yeshiva like Gateshead will make itself felt: scrubbing away the moderation that Sephardim and Mizrahim treasure. Moderate Orthodoxy is not manna, it must be made and trained.

More is at stake here than a few haunting melodies and the order of the prayers. What really divides classical Sephardic and Ashkenazi Judaism is an approach not to what happens in the synagogue but what happens outside them. Where old Ashkenazi Rabbis would shun the courts of German and Polish counts and kings as corrupting; old Sephardic Rabbis would embrace the Islamic courts of Cordoba and Toledo. Maimonides was the Sultan’s physician. This is because a fundamental attitude towards the Torah divides the two. Sephardim and Mizrahim have always treated the Torah as a guide into the world and not — like the Ashkenazim — a wall against the world. Everything that makes Mediterranean and Middle Eastern Judaism so beautiful — the food, the pride, the love of this life — stems from this precious subtlety.

Ben Judah is the author of This is London