The top of a tattooed number 6 is still visible on his left forearm. David Wisnia had the rest of "83526" removed by a plastic surgeon.
It was a reminder of three dark years spent in the Auschwitz concentration camp, where he witnessed unimaginable horrors.
Wisnia, 88, of Levittown, remembers collecting bodies of fellow prisoners who had tried to escape and were gunned down.
He recalls his Nazi captors' orders to retrieve money and valuables from the clothes shed by countless people before they were shot or gassed.
And he recollects the uprising of prisoners who attacked guards at Crematorium 4, believing they had nothing to lose because they were on their way to a gas chamber.
What saved Wisnia, then 16, at Auschwitz-Birkenau in Nazi-occupied Poland was a strong singing voice. He used it to entertain the SS guards.
That voice - honed as a boy in a Warsaw synagogue - will be heard again in the camp during ceremonies Jan. 27 marking the 70th anniversary of the liberation of Auschwitz.
Wisnia, a cantor who has inspired listeners at Philadelphia-area synagogues, at a retirement home in Trenton, and at annual High Holy Days gatherings in Jackson, N.J., will sing a memorial to those who died at a camp site known as "death's door."
He will be there at the invitation of the government of Poland, which is paying for his trip. Representatives of about 100 countries are expected to attend.
He will also sing at a service Jan. 24 - accompanied on the piano by his grandson - at the Beit Polska synagogue in Warsaw.
"Of course you never forget," said Wisnia, whose parents and two brothers were killed by the Nazis. "I managed to isolate what I saw and put it in the back of my mind.
"I was in Auschwitz close to three years," he said. "There are very few who can boast that."
Wisnia later escaped the Nazis and stumbled into the U.S. Army's 101st Airborne Division, soon becoming the unit's official interpreter. The old veterans still call him "Little Davy."
"I started my new life with the 101st Airborne," said Wisnia, who will attend the unit's Feb. 4 reunion in Tampa, Fla., where he will sing the national anthem. "They were my family."
With help from New Jersey educators Robin Black and Doug Cervi, Wisnia has been finishing his memoir, expected to be released this year.
"We, as a world community, need to study [the Holocaust] a lot more than we're doing right now," said Cervi, an adjunct professor at Richard Stockton College in Galloway Township, where in the spring he will teach the impact of the genocide, which resulted in the deaths of about six million Jews. "If we don't learn lessons from this, night will fall again."
Auschwitz was a network of Nazi concentration and extermination camps where historians estimate between 2.1 million and 4 million people died, the vast majority Jews. Only about 200,000 survived the Auschwitz camps, including 65,000 at Birkenau.
Wisnia's introduction to life there came after family members were killed as they were being rounded up in December 1941 in the Warsaw ghetto. His 41-year-old carpenter father, 37-year-old mother, and 14-year-old brother were shot to death. His 19-year-old brother was later killed as he tried to escape the Treblinka extermination camp in Poland.
But Wisnia survived and was transported to Auschwitz with about 1,500 others. He was one of about 570 young, able-bodied men who were selected as laborers. The rest - women, children, and elderly - were executed.
Because of his fine singing voice and fluent German, Wisnia was chosen as the camp's entertainer. In addition to Polish, he spoke French, Hebrew, and Yiddish.
"I sang in German for the cell-block leaders and entertained the SS in the main guard houses in Birkenau. It saved my life," said Wisnia, who later served as cantor at Temple Shalom synagogue in Levittown and Har Sinai synagogue in Trenton.
"I got a cushy job after the first year," he said. "I sorted the clothes. I was supposed to look for money."
Wisnia was sorting clothes on Oct. 23, 1943, when he witnessed the unthinkable - the deadly revolt at Crematorium 4.
A group of prisoners, including the Polish Jewish dancer Franceska Mann, were taken into a room next to a gas chamber and ordered to strip.
Mann apparently grabbed the roll-call officer's pistol, fatally wounding him in the stomach, according to some accounts. She also reportedly fired a shot that wounded an SS sergeant. A revolt by the other prisoners was broken up when guards mowed them down with machine guns.
As the months passed and artillery began to sound in the distance, the Nazis began moving the prisoners in what Wisnia called the "death march." In December 1944, they walked to Gleiwitz, Poland, to board a train to the Dachau concentration camp in Germany.
"That was a very bad sign for me," he said. "I survived so many years, and now the war was coming to an end.
"Dachau was chaos personified," he said.
Wisnia volunteered to help excavate bunkers to house the new German jet fighters and was being transported on a railcar when planes with white stars strafed them.
He escaped when the train stopped. He hid in barns by day and walked toward the sound of the guns at night.
"One fine morning, I heard the roar of tanks, and I prayed, 'Let there not be swastikas or black crosses on those tanks,' " Wisnia said.
The tanks marked with white stars stopped, and he joined the ranks.
Wisnia quickly learned English, became the unit's official interpreter, and was issued a uniform and gun.
By 1946, he had come to the United States, settling first in New York and later Mount Airy, then Levittown.
He married in 1948, had four children, and was vice president of sales for a New York publishing company until four years ago. He is cantor emeritus at Har Sinai synagogue in Pennington, N.J., and continues to serve at weddings, funerals, and other events.
But memories of Auschwitz are never far from his mind. In 1956, he returned to the camp for the first time and etched his name on the wooden shelf where he once slept.
In 2004, he began giving annual talks about his experiences to students at Oakcrest High School in Mays Landing. "You could have heard a feather drop," said Cervi, who was a history teacher there when Wisnia addressed a class of 25.
The next year, Wisnia spoke to 400 in the auditorium. "The kids stood up and gave him a standing ovation," Cervi said.