Marking the 65th anniversary of the liberation of Auschwitz, President Obama said the death camp invokes a “sacred duty” to remember Nazi crimes.

“We have a sacred duty to remember the twisted thinking that led here, how a great society of culture and science succumbed to the worst instincts of man and rationalized mass murder and one of the most barbaric acts in history,” Obama said in a video message to be delivered at International Holocaust Remembrance Day commemorations Wednesday. “We have a sacred duty to remember the cruelty that occurred here, as told in the simple objects that speak to us even now. The suitcases that still bear their names. The wooden clogs they wore. The round bowls from which they ate. Those brick buildings from which there was no escape, where so many Jews died with Sh’ma Israel on their lips.”

Leading the U.S. delegation to the commemoration is Julius Genachowski, the chairman of the Federal Communications Commission and the child of survivors.

Others in the delegation include Lee Feinstein, the U.S. ambassador to Poland; Hannah Rosenthal, the special envoy to combat and monitor anti-Semitism; Susan Sher, First Lady Michelle Obama’s chief of staff and the liaison to the Jewish community; Roman Kent, the chairman of the American Gathering of Jewish Holocaust Survivors and a survivor of Auschwitz; and Auschwitz survivors Charlene Schiff and Edwarda Sternberg-Powidzki.