There was a distinct body of Roman Catholics who hoped that Cardinal Jean-Marie Lustiger, the Archbishop of Paris, might one day become Pope. Some felt, in humorous vein, that thus, in answer to the rhetorical sally “Is the Pope a Catholic?”, the riposte might be: “Actually, he’s a Jew.”

There had also been a prophecy by the Irish seer Malachi that a Jewish Pope would follow Peter after two millennia.

Indeed, during the papal elections of 2005, the bookies gave Cardinal Lustiger more than a sporting chance, as second favourite to Joseph Ratzinger, with odds of 9-2. But in truth, the French Cardinal was already ailing and indicated that on health grounds he would not be papabile.

Had he been elected by the College of Cardinals as pontiff, it might have been a controversial choice — certainly with those Jews who felt that Lustiger had “betrayed” his ancestral faith by converting to Roman Catholicism in his youth.

In Israel in 1995 Lustiger was bitterly denounced by the Chief Rabbi for “betraying his people and his religion”: this view was supported by the former Chief Rabbi of Britain, Lord Jakobovits. But Lustiger did not see his commitment to Catholic Christianity in that light: perhaps more correctly, from a historical viewpoint, he saw Judaism and Christianity as root and branch, made from the same weave. He never betrayed Judaism in the sense that he always proclaimed his Jewishness with candour and pride. But he had become a Catholic as an adolescent, and in traumatic and sorrowful circumstances; and his commitment was deep and enduring.

As a preacher — he would usually fill Notre Dame cathedral when celebrating Mass — he was warm, human and often funny. That Jewish sense of humour was, after all, also part of his heritage. He was much admired, liked and promoted by Pope John Paul II, whose final thoughts on this earth were of the Jewish playmates of his youth.

Aaron Lustiger was born in Paris in 1926, the only son of Charles and Gisèle Lustiger, whose families had migrated to France from Bedzin in southern Poland after the First World War. The Lustigers started out as modest market traders: subsequently, Gisèle, a gifted milliner, acquired a hat shop in the Montmartre area. Aaron was sent to the highly respected Lycée Montaigne, where he was an outstanding student. The Lustigers were secularised Jews, and Aaron received no religious instruction as a child: but the interest in faith was in his nature, and he discovered the Bible for himself in the course of his reading.

When he was 13, at a time when Orthodox Jewish boys would be having their bar mitzvah, Lustiger visited the Catholic cathedral in the city of Orléans — whither his parents had fled after the outbreak of the Second World War — and felt immediately drawn to its ambience. He was permitted to convert to Catholicism in 1940, not least because it seemed a wise course during the anti-Semitic Vichy regime — and took the Christian name Jean-Marie. Subsequently his sister Arlette also became a Catholic. In the early phase of the war the Lustiger siblings were fostered by a Catholic family in the Orléans area, and protected by the Bishop of Orléans, Jules-Marie Courcoux.

Tragically, Gisèle Lustiger decided to return to Paris, where she was betrayed to the Vichy authorities by her own maid; she was deported to Auschwitz, where she perished. Charles Lustiger survived the war by staying in the South of France but he came to feel that his son had converted to Catholicism under duress, and at an impressionable age. Jean-Marie was stubbornly insistent that his conversion came from a strong inner commitment, and resisted all efforts by his father, supported by the Chief Rabbi of Paris, to abandon his Christian conversion.

After graduating from the Sorbonne Lustiger entered a Carmelite seminary in Paris and was ordained a priest at the age of 28, in 1954. He became a chaplain at the University of Paris and subsequently a director of the Richelieu Centre, an institute for academic chaplains.

In the postwar years when Paris was abuzz with intellectual ferment, with strong left-wing and Existentialist influences, Lustiger’s cast of mind was conservative: one of his ideas, which later became influential, was that the Enlightenment, far from freeing men’s minds, was responsible for much of the rise of despotism, extreme nationalism and racism. As with Friedrich Hayek, these themes did not receive their due attention until after the fall of communism in 1989.

Lustiger was appointed rector of a parish in the 16th arrondissement, St Jeanne de Chantal, in 1969, where he first gained a reputation as a fine preacher. Soon after his election as Pope in 1978, John Paul II appointed Lustiger to be Bishop of Orléans, and on January 31, 1981, he was promoted to Archbishop of Paris.

By the late 1970s the son had been reconciled with his father, and when Charles Lustiger died, his son organised a Jewish funeral for him.

Cardinal Lustiger was, like John Paul II himself, a mixture of traditionalist and moderniser: he was regarded as authoritarian in some measures and had some difficult relations with more liberal ecclesiastics. But he was also supportive of the charismatic movements, was strong in his anti-racist values, and was highly aware of the importance of modern media, encouraging Catholic radio and TV channels.

He was fearless in defending Catholic schools against an aggressively secularising Minister of Education, Alain Savary, and in 1984 organised a large and successful public rally to protest against the reduction in aid to religious schools. Savary was subsequently obliged to resign.

Lustiger’s relations with President François Mitterrand were cordial: Mitterrand claimed to be agnostic, but the values of the French peasant went deep, and he sought a Catholic funeral, over which Cardinal Lustiger presided with distinction.

Lustiger retired on February 11, 2005, the feast of St Bernadette of Lourdes. He was the author of 20 books and in 1995 he had the distinction of being elected to the Académie Française. He had also been awarded the Lebanese Order of the Cedar, and the Sovereign Order of Malta. In 1998 he had been awarded the Nostra Aetate Award for advancing Catholic-Jewish relations by the Centre for Christian-Jewish Understanding in the United States.

At his death the World Jewish Congress paid a tribute to the Jewish cardinal, whose sincere commitment to the Catholic faith never precluded his pride in his Jewish heritage.

Cardinal Jean-Marie Lustiger, Archbishop of Paris, 1981-2005, was born on September 17, 1926. He died of cancer on August 5, 2007, aged 80