BERLIN — Pope Benedict XVI addressed the German parliament in the historic Reichstag building Thursday, warning that politicians must not sacrifice ethics for power and evoking the Nazi excesses of his homeland as a lesson in history.
Amid scattered protests outside and a boycott by some lawmakers, Benedict began his first state visit to Germany in a bid to stem the tide of Catholics leaving the church while acknowledging the damage caused by the clerical sex abuse scandal.
The pope spoke for 20 minutes in the Reichstag, which was torched in 1933 in an incident used by Adolf Hitler to strengthen his grip on power.
"We Germans know from our own experience" what happens when power is corrupted, Benedict said, describing Nazis as a "highly organized band of robbers, capable of threatening the whole world and driving it to the edge of the abyss."
He also urged all Germans not to ignore religion.
"Even today, there is ultimately nothing else we could wish for but a listening heart - the capacity to discern between good and evil, and thus to establish true law, to serve justice and peace," he said.
After the speech, he met with a 15-member Jewish delegation, noting that it was in Berlin that the annihilation of European Jews was organized.
"The supposedly 'almighty' Adolf Hitler was a pagan idol, who wanted to take the place of the biblical God," Benedict said according to a prepared text.
The Bavarian-born pontiff was met on a red carpet at Berlin's Tegel airport by German Chancellor Angela Merkel and President Christian Wulff at the start of his four-day visit. He greeted members of the German Catholic Church and accepted a bouquet from children waiting with small yellow-and-white Vatican flags.
About 20 protesters stood outside the airport, holding banners with slogans such as "Against anti-Semitism, sexism and homophobia" and "My body, my choice."
The Vatican's views on contraception, the role of women and homosexuality and its handling of the sexual abuse scandal that rocked Germany last year are seen by Catholic critics in Germany as outdated.
About 100 lawmakers from opposition parties boycotted the pope's appearance, claiming it violated the church-state separation. But Benedict looked out on a mostly full house as guests occupied the empty seats, and he finished his speech to a standing ovation.
Police estimated just "several thousand" protesters showed up at the capital's Potsdamer Platz, far fewer than organizers had predicted. About 6,000 officers were on duty throughout the city.
Flagging Christian influence in Europe was one of Benedict's key themes.
"We are witnessing a growing indifference to religion in society," he said at a formal welcoming ceremony at the German president's Bellevue Palace.
He called religion a foundation for a successful society and said its values were essential for freedom.
Over the next four days, the pope is scheduled for meetings with leaders of Germany's Jewish and Muslim communities, three Masses and an ecumenical service with Lutheran Church members.
More than 250,000 people are registered attend his Masses, starting with an open-air service Thursday night in Berlin's Olympic Stadium, built by the Nazis for the 1936 Olympic Games. About 70,000 enthusiastically cheered the pope as he drove through the stadium in his popemobile, greeting the faithful and kissing several babies.