In the past five years, Warsaw’s Jewish community had grown to 600 families from 250. The cafes and bars of the old Jewish quarter in Krakow brim with young Jewish converts listening to Israeli hip hop music.

Michal Pirog, a popular Polish dancer and television star, who recently proclaimed his Jewish roots on national television, said the revelation had won him more fans than enemies. “Poland is changing,” he said. “I am Jewish and I feel good,” he said.

Pawel’s metamorphosis from baptized Catholic skinhead to Jew began in a bleak neighborhood of concrete tower blocks in Warsaw in the 1980s, where Pawel said he and his friends reacted to the gnawing uniformity of socialism by embracing anti-Semitism. They shaved their heads, carried knives and greeted one another with the raised right arm gesture of the Nazi salute.

“Oy vey, I hate to admit it, but we would beat up local Jewish and Arab kids and homeless people,” Pawel said on a recent day from the Nozyk Synagogue here. “We sang about stupid stuff like Satan and killing people. We believed that Poland should only be for Poles.”

One day, he recalled, he and his friends skipped school and took a train to Auschwitz, the Nazi death camp, near Krakow. “We made jokes that we wished the exhibition had been bigger and that the Nazis had killed even more Jews,” he said.

Even as Pawel embraced the life of a neo-Nazi, he said that he had pangs that his identity was built on a lie. His churchgoing father seemed overly fond of quoting the Old Testament. His grandfather hinted about past family secrets.

“One time when I told my grandfather that Jews were bad, he exploded and screamed at me, ‘If I ever hear you say such a thing again under my roof, you will never come back!’ ”