ROME — In comments on Sunday that could have broad implications in a period of intense religious conflict, Pope Benedict XVI cast doubt on the possibility of interfaith dialogue but called for more discussion of the practical consequences of religious differences.
The pope’s comments came in a letter he wrote to Marcello Pera, an Italian center-right politician and scholar whose forthcoming book, “Why We Must Call Ourselves Christian,” argues that Europe should stay true to its Christian roots. A central theme of Benedict’s papacy has been to focus attention on the Christian roots of an increasingly secular Europe.
In quotations from the letter that appeared on Sunday in Corriere della Sera, Italy’s leading daily newspaper, the pope said the book “explained with great clarity” that “an interreligious dialogue in the strict sense of the word is not possible.” In theological terms, added the pope, “a true dialogue is not possible without putting one’s faith in parentheses.”
But Benedict added that “intercultural dialogue which deepens the cultural consequences of basic religious ideas” was important. He called for confronting “in a public forum the cultural consequences of basic religious decisions.”
The Vatican spokesman, the Rev. Federico Lombardi, said the pope’s comments seemed intended to draw interest to Mr. Pera’s book, not to cast doubt on the Vatican’s many continuing interreligious dialogues.
“He has a papacy known for religious dialogue; he went to a mosque, he’s been to synagogues,” Father Lombardi said. “This means that he thinks we can meet and talk to the others and have a positive relationship.”
To some scholars, the pope’s remarks seemed aimed at pushing more theoretical interreligious conversations into the practical realm.
“He’s trying to get the Catholic-Islamic dialogue out of the clouds of theory and down to brass tacks: how can we know the truth about how we ought to live together justly, despite basic creedal differences?” said George Weigel, a Catholic scholar and biographer of Pope John Paul II.
This month, the Vatican held a conference with Muslim religious leaders and scholars aimed at improving ties. The conference participants agreed to condemn terrorism and protect religious freedom, but they did not address issues of conversion and of the rights of Christians in majority Muslim countries to worship.
The church is also engaged in dialogue with Muslims organized by the king of Saudi Arabia, a country where non-Muslims are forbidden from worshiping in public.
A version of this article appeared in print on November 24, 2008, on page A7 of the New York edition.