So around the fifth century, a group of rabbis known as Masoretes (masoret is Hebrew for tradition) gathered in Tiberias to pin tropes, or musical signs, to every word of holy writ. These tropes are still sung wherever Jews gather to pray. The tune varies considerably, influenced by the host culture. In a German community it will be tonal, among Iraqis microtonal. The system, though, remains the same and the phrasing is identical wherever Torah is sung. Musical notation saved the Jews from oblivion.

Bearing that lesson in mind, Jews came to regard music as a defence mechanism for their civilisation. Evicted from Spain and Portugal in 1492 and 1497, they carried away a bevy of Iberian melodies and liturgies in their hybrid language, Ladino. Oppressed in the Russian Empire, they absorbed indigenous themes and gave them a Jewish specificity. A march song of the invading French army in 1812 was renamed the Napoleon Nigun and sung by Lubavitch Chasidim at the climax of their religious devotions, the end of Yom Kippur.

The entry of Jews into European music was resisted by Church and state until the post-Napoleonic era, when two Berliners, Meyerbeer and Mendelssohn, burst into opera and symphonic music with irresistible force. Within two generations, Gustav Mahler was reforming the Vienna Opera and Arnold Schoenberg had torn off the tonal corset of the western canon, replacing it with a liberated atonality.

On New York's Lower East Side, sons of Russian pogrom refugees and former plantation slaves turned a common tendency to sing "blue" notes in minor keys into an industry of popular music. George Gershwin, a genius of fusion, named some of his themes as "freygish" — the interrogative melody of Talmud study (musicologists thought he meant the Phrygian mode). In the Bible-sceptical It Ain't Necessarily So, Gershwin simultaneously exalts and challenges his ancestral civilisation.

Resistance to the upsurge of Jews in music found violent expression in Richard Wagner's writings and violent reaction in Hitler's Europe. Jews were accused of lacking musical originality and remoulding public taste. There is a grain of truth in these charges. Michael Grade, born into an entertainment dynasty, maintains that Jews invented the music business because their history had taught them to be one step ahead of the popular mood, ugly as it might turn.

An Israeli composer, visiting Bayreuth, exclaims: "Wagner was right! We don't hear music in the same way as they do." A Mahler symphony is open to conflicting interpretations. An Amy Winehouse song exposes a grief older than her own. The interaction of music and the Jews is a fertile engagement of primal, nebulous forms, a mystic glimpse of infinite possibilities.