A prayer for the conversion of the Jews sidelined from Roman Catholic liturgy in the 1960s may stage a surprise comeback tomorrow, when Pope Benedict is expected to allow broader use of the old Latin Mass.
Church reforms in the 1960s replaced Latin with local languages in the liturgy, reached out to other religions and struck texts that Jews found particularly offensive, such as a Good Friday prayer referring to "perfidious Jews".
Pope Benedict's decree is due to revive a 1962 Latin prayer book that removed the word "perfidious" but left standing prayers for their conversion that ask God to "take the veil" off Jewish hearts and show mercy "even for the Jews," Church sources said.
The decree aims to woo back traditionalists devoted to the old Latin rite. The move is controversial among Catholics, since many traditionalists reject the reforms of the Second Vatican Council (1962-1965) including the opening to other faiths.
Abraham Foxman, National Director of the Anti-Defamation League (ADL), a US-based Jewish civil rights group, was cautious ahead of the publication of the document.
"From second-hand sources, my understanding is they understand our concern, our sensitivity, our distress," Mr Foxman said in Rome. "And I think they're not about to add to that distress after all the efforts we've made with reconciliation."
The Pontiff's motu proprio decree is expected to allow priests greater freedom to opt for the Latin mass. Currently, priests have to seek authorisation from bishops to use the so-called Tridentine mass and many refuse to give it.
Some Catholics are worried that this nod to traditionalists may undermine the liberal reforms of the Second Vatican Council, known as "Vatican II."
"Inevitably it will be read by some people as a victory for those who felt that Vatican II was a mistake," said Father Keith Pecklers, a Rome-based Jesuit liturgical expert, adding this "of course is not the intention".
When Pope Benedict met a group of cardinals last month to explain his decision, he told them he was trying to draw in many of an estimated 600,000 Catholics who left the Church after Vatican II to attend Latin masses said by traditionalist priests.
"By making the Latin Mass more available, the Holy Father is hoping to convince those disaffected Catholics that it is time for them to return to full union with the Catholic Church," Boston Cardinal Sean O'Malley wrote in his blog after the meeting.
The traditionalists are strongest in France and bishops there have openly criticised the return to Latin, saying it could encourage traditionalists to continue challenging the Vatican II reforms and result in deeper splits in the Church.
The liberal French Catholic magazine Temoignage Chretien published an editorial in Latin this week criticising the Vatican for fostering two liturgies within one Church.
It said what concerned them was not aspects like the Latin of the Tridentine rite, but "the view of the outside world held by most supporters of the traditional rite ... of a Church that saw itself as the sole holder of the Truth."
"Forty years after the Second Vatican Council, this stand is untenable," it wrote.