ROME – Two new discoveries regarding Pope Pius XII are rekindling debate over the role of the wartime pontiff, including a letter suggesting he had earlier knowledge of the Holocaust than previously believed and a Nazi dagger presented to the pontiff by a repentant SS officer.

Both items were published in a Sunday insert of Corriere della Sera, Italy’s paper of record, after have been discovered by a researcher in the Vatican archives and made public with the encouragement of Vatican officials.

The yellowed letter, dated Dec. 14, 1942, was written by an anti-Nazi German Jesuit named Father Lothar König and addressed to the personal secretary of Pope Pius XII, another German cleric named Father Robert Leiber.

In the letter, König reports that an estimated 6,000 Jews and Poles were being killed every day at the Belzec concentration camp in what was then German-occupied Poland, today western Ukraine. König refers to the operation of “blast furnaces” at the camp, and also makes a passing mention of the Auschwitz and Dachau camps, referring to another report which, for the moment, has not been found.

The letter makes its more difficult to sustain, as some apologists for Pius XII have in the past, that the wartime pontiff did not explicitly and publicly condemn the Holocaust because he had only scattered and conflicting reports about the extent of the Nazi genocide.

The letter is part of a new trove of documents now available to researchers after Pope Francis decided in March 2000 to open all the archives from Pius XII’s reign, which ran from 1939 to 1958. Researcher Giovanni Coco, an official of the Vatican archives who discovered the letter, emphasized the importance of these materials.

“For a half-century, we’ve argued about indirect documents and sources,” Coco told Corriere della Sera. “Now we have direct sources, and others probably will emerge. We’re trying to render them as accessible as possible to everyone, so the terrible season in which Pius XII guided the Church can be understood.”

“Everything must come out, without fears or prejudices,” Coco said.

In the same interview, Coco also revealed the existence of a dagger with the Nazi swastika which had been discovered in Pius XII’s private apartment after his death by his successor, Pope John XXIII. According to Coco, the new pope asked for an explanation of the dagger from then-Archbishop Angelo Dell’Acqua, who at the time was the substitute in the Secretariat of State, effectively the pope’s chief of staff.

Dell’Acqua in turn asked Sister Pascalina Lehnert, a German member of the Sisters of the Holy Cross who acted as Pius XII’s housekeeper and advisor from the period when the future pope was the Vatican’s ambassador in Bavaria in 1917 until his death. During the war years, Lehnert coordinated efforts to shelter Jews in church facilities on behalf of Pius XII.

Coco said that Lehnert explained that the dagger had been brought to a papal audience by an SS officer, who had planned to use it to attack the pontiff. Instead, Lehnert said, the SS officer had a change of heart and presented the dagger to the pope as a sign of repentance.

An image of the dagger was reproduced in the Corriere della Sera insert.

Over the years, critics of Pius XII have objected to what they describe as his “silence” on the Holocaust, while supporters claim he acted behind the scenes to save Jews and other Nazi victims. Asked to explain Pius XII’s discretion in terms of issuing public statements, Coco said that “several fears had an impact.”

Among those concerns, Coco said, was the concrete possibility of reprisals against Catholics in Poland should the pope directly condemn the operation of Nazi death camps on their territory.

“It would have meant severing relations with the bishops of a community already under the Nazi heel,” Coco said.

The researcher also acknowledged that anti-Semitism may have played a role.

“In a large part of the Vatican world, prejudice against Jews stagnated, not only on a religious level, but sometimes also anti-Semitic,” Coco said.

The 1942 letter is part of a broader set of papers from Pius XII’s papacy set to be published by the Vatican archives today. It will also likely be discussed at an Oct. 9-11 international conference at Rome’s Jesuit-run Gregorian University titled, “The new documents from the pontificate of Pous XII and their significance for Jewish-Christian relations.”