We like our religion dark and dangerous, at least according to trends in contemporary fiction. Since Dan Brown's The Da Vinci Code - the best-known example - a steady stream of conspiracy thrillers has fed our fascination with ancient scrolls, secretive sects and Templar knights.
In his debut novel, The Righteous Men, Sam Bourne (alias Jonathan Freedland) gave the genre a Jewish twist. A seemingly inexplicable chain of murders turns out to involve an old legend that in every generation there are 36 righteous men without whom the world could not continue to exist. The 36 have cropped up in tales across the centuries, but perhaps there is more to them than simply being the stuff of Yiddish folklore or modern murder mystery.
The idea of a small group of virtuous men on whom depends the fate of a whole society goes back to the Bible when Abraham haggles with God over Sodom, slated for destruction because of its depravity. If 50 righteous men can be found there, will God not spare it on their behalf, the patriarch argues. Abraham persists in his plea-bargaining until he whittles the number down to 10 (though even this proves beyond the city's wicked inhabitants).
The figure 36 appears first in the Talmud, when a fourth-century rabbi, Abaye, suggests that every generation must contain this minimum number of people who are able to experience the divine presence. Abaye, with a typical piece of rabbinic creativity, derives it from the conclusion to a verse in Isaiah (30:18), "Happy are they who wait for Him." The numerical value of the two Hebrew letters which spell "him" comes to 36.
Typically, too, for the Talmud, there is a difference of opinion among the rabbis. Another sage proposes that there are 45 men "on account of whom the world continues to exist".
Yet another alternative is 30, based on the interpretation of a verse in Genesis (18:18), when God promises Abraham he will become a great nation in whom all the families of the world will be blessed: the numerical equivalent of the word "become" in Hebrew is 30.
But it was 36 which eventually stuck. One theory is that this represents a majority vote at the Sanhedrin, the Supreme Rabbinic Court of 70 judges, which tradition says will be reconstituted in the messianic era.
The great modern scholar of Jewish mysticism, Gershom Scholem, however, cites an entirely different explanation: the number could have been absorbed from ancient astrology, which divided the 360 degrees of the heavenly circle into 36 segments called deans, each presided over by a divinity.
Whatever their origin, the righteous crew came to be known after the two Hebrew letters representing 36, lamed and vov, or lamedvovniks in Yiddish. You can hear the word used colloquially in the eulogy scene in A Serious Man, the Coen brothers' 2009 film.
By the time lamedvovniks were popularised in 18th and 19th century Yiddish stories, they had taken on a key characteristic: their membership of this elite group of righteous, scattered among the nations, remained a closely-guarded secret. They were "seemingly ordinary people, usually artisans living in little villages, who do not know the identity of the other 35 and may not even know that they themselves are part of the charmed circle," explains Rabbi Louis Jacobs in The Jewish Religion: A Companion.
Scholem speculates that their anonymity may have come from the tradition of hidden saints among Islamic mystics in early medieval times; alternatively, it could be based on an older Jewish source which passed across the Middle East and then entered Islam.
According to the folk tales, one of these spiritual superheroes would sometimes arrive on the scene to help his co-religionists at a time of distress. In one tradition, every generation of 36 includes one among them who is a Messiah-in-waiting, with the potential to be revealed as Israel's long-awaited redeemer. (Thus some Lubavitch Chasidim are able to believe that their last leader, Menachem Mendel Schneerson, was the Messiah and, despite his apparent death in 1994, await his coronation yet.)
The lamedvovniks took their place as part of the imaginative repertoire which helped Jews to sustain their messianic hopes amid the travails of the diaspora. But the myth may also convey a certain ideal, subversive in its way, of the spiritual life.
The whole point of undercover saints is that they stay hidden. Dwelling among the ordinary rank and file, they preserve their saintliness only by remaining outside established religious institutions. We may build edifices of ecclesiastical authority, hierarchies of piety, but the tradition of the lamedvovniks teaches that a spiritual leader should be humble enough to recognise that any of his congregants may be more righteous than him.
If the idea of a select band of individuals seems elitist, in practice it imposes equality since everyone must live with the possibility than any one else might be one of the chosen few. The tradition implies a certain attitude towards other people. If the true face of righteousness remains hidden from public view, then you can never be sure who genuinely represents it.
So beware of dismissing others and treat everyone with respect. For you never know. As Scholem says, "Your neighbour may be one of the hidden just men."