Born in Ukraine around 1880, Moïse Twersky was the son of a Hasidic rabbi from the Zadik lineage, those "miraculous rabbis" who exercised spiritual and judicial authority over vast Jewish communities in Eastern Europe. His father was the rabbi of Bila Tserkva (Schwarzé-Témé) in Ukraine. Considered a descendant of King David, he possessed a silver throne and presided over meals of 250 guests every Saturday.
Destined for this succession, young Moïse became passionate about forbidden books and discovered modern science. He categorically refused to perpetuate what he now considered an exploitation of popular credulity and decided to become a chemist. At sixteen, he was married according to tradition to a thirteen-year-old girl, daughter of a Romanian rabbi. Against all expectations, he fell in love with her, but the discovery of his heretical readings forced his separation from his young wife.
Twersky studied chemistry in Brussels then emigrated to the United States where he experienced extreme poverty, working notably in a canning factory where the salt from the casings he handled daily burned his hands. The circumstances of his return to Europe remain obscure.
In Paris, he established himself as a translator of the English press for a sugar manufacturers' syndicate, earning 600 francs per month. He lived in a small apartment on rue Oudry, near Les Gobelins, and led an austere but free existence. Refusing the constraints of better-paid employment, he jealously preserved his independence. He assiduously frequented the milieu of émigré Jewish intellectuals, discussing politics and philosophy.
In the 1910s-1920s, Twersky frequented the Café Soufflet where he became the informant for the Tharaud brothers for their novels about the Jewish world of Eastern Europe. His intimate knowledge of Hasidic communities provided them with exceptional documentation. Paradoxically, he became the main anonymous source for the brothers' antisemitic novels whose picturesque and repulsive "Jewish vein" would contribute to the normalization of hatred of Jews in France.
Thanks to Twersky, his strange friends recount, "a table on the first floor of Café Soufflet became, by a kind of very real miracle indeed, a corner of a Carpathian village, the pond where geese frolic, the rabbi's palace, a synagogue at prayer time, with its songs and vociferations, the ritual bath". (La double confidence, J. and J. Tharaud)
When he became aware of the antisemitic use they made of his testimonies, Twersky broke with the brothers and subsequently collaborated with writer André Billy on a novel trilogy, The Epic of Ménaché Foïgel, published under both their signatures: Le fléau du savoir (1951), Comme Dieu en France and Le lion, l'ours et le serpent. The title metaphorically evokes the thirst for knowledge that tears young Jews from their traditional world – his own journey. Unlike the Tharauds, Billy insisted that Twersky co-sign the work, refusing an anonymous collaborator.
On the day the Germans entered Paris, in June 1940, Moïse Twersky took his own life in his apartment on rue Oudry. He had confided to André Billy that in old age, he would "blow his brains out" – a statement made "very simply and with a broad smile". Facing the collapse and persecutions he foresaw, this man of "cold and logical intelligence" chose suicide over decline. The exact circumstances of his death vary according to sources. André Billy reports a suicide by Veronal, while his « friends » the Tharauds, in their 1951 memoirs, attribute to him another death, of dubious irony: "the idea that the persecutions taking place in Germany would soon begin in France, this idea was unbearable to him. (...) Moïse Twersky took his own life, not with a revolver, but with the gas from the small kitchen in his apartment."
