Encouraging Muslim guests at a recent Friday evening dinner in Warsaw to join in the refrain of a traditional Shabbat song by chanting “la, la, la,” the American Jewish Committee’s Rabbi David Rosen was briefly interrupted. Dr. Mohammad al-Issa, secretary-general of the Muslim World League, pointed out that the word “la” in Arabic means “no.” He suggested using the word “naam,” yes. Without further delay, Rosen led the 100 people gathered at Warsaw’s Royal Castle in the revised and uplifting chorus.The festive evening capped a groundbreaking interfaith mission to Poland that began the day before with a visit to Auschwitz to deepen understanding of the Holocaust. It was followed by a full day in Warsaw visiting sites to mark and celebrate the Polish Jewish civilization that was, and the small but vibrant Jewish community which has reemerged. What participants saw and heard at Auschwitz and Birkenau was on the minds of all and reflected clearly in Issa’s remarks at the Polin Museum of the History of Polish Jews, the Tatarska Street Mosque, the Nozyk Synagogue and, finally, at the Shabbat dinner.“We condemn the horrific acts that took place at Auschwitz against the Jews. It is a stain on humanity,” said Issa. “The evidence we saw yesterday shook us all. It was so painful for me looking at human hair, at children’s shoes, at so much more evidence of the atrocity.”Issa called those around the world who engage in Holocaust denial “partners in the crime. They are like Nazis themselves.”The genesis of the trip was a groundbreaking memorandum of understanding signed last April by American Jewish Committee CEO David Harris and Issa, who traveled from Mecca to AJC headquarters in New York. Visiting Auschwitz was the first joint action implementing the MOU. “The launch of cooperative projects by AJC and MWL [Muslim World League], and Issa’s visit to Auschwitz, is a direct rebuttal to the extremists who threaten us all,” Harris said. “By educating people on the horrors of history, we can plant the seeds for a future where Jews, Muslims and all other groups can live free of fear.”Harris, the son of survivors, has headed the leading global Jewish advocacy organization since 1990, and spearheaded initiatives to preserve the memory of the Shoah, ensuring that the words “Never Again” are meaningfully understood and realized.Issa had thought the trip would be so important that he assembled a large delegation of 62 Muslims, including 25 prominent religious leaders, from 28 countries on several continents. Indeed, it was the most senior Islamic leadership delegation to ever visit Auschwitz or any Nazi German death camp. Significantly, Issa brought several leading Arabic TV and other media outlets that provided extensive, positive coverage across the region.The joint visit was transformative for both Muslim and Jewish participants. While both sides may have had questions, uncertainties about the nascent relationship in advance of the trip, by Friday evening both Harris and Issa were referring to one another as partners. Indeed, the visit confirmed the potential for further joint efforts by AJC and the MWL.The January 23 visit purposely took place a few days before the official ceremonies at Auschwitz marking the 75th anniversary of the liberation of the camp where more than 1.1 million, including approximately 100,000 non-Jews, were systematically murdered. With the numbers of aging survivors and witnesses to the Holocaust rapidly dwindling, learning what happened and, if possible, visiting the sites where the Nazi genocide of Jews occurred become increasingly important.INDICATIVE OF the current and future challenges Jews and others will face in preserving the memory of the uniqueness of the Holocaust was a new Pew Research Center survey that revealed a disturbing lack of basic knowledge among Americans about the Holocaust. Only 45% answered correctly that six million Jews were murdered. Nearly a third, 29%, said they were not sure or did not answer, while 12% said it was about three million, 2% selected less than one million, and 12% said more than 12 million Jews died in the Holocaust. As new initiatives are undertaken to bring awareness of the indisputable facts and reality of the Holocaust to new audiences, especially in the Muslim world, where the Jewish narrative has long been ignored, the Pew survey, confirming the findings of an earlier Claims Conference survey, was a reminder that understanding of the Holocaust should never be taken for granted, notwithstanding mandatory education in a number of US states and the existence of museums and memorials across the country.The AJC-MWL joint interfaith mission to Auschwitz was a first, and major, step toward developing understanding and empathy in the Muslim world for the Jewish people.The writer is the AJC’s director of media relations.