Pope Benedict has warned Germans of the danger of ignoring religion as he began his first state visit to his native country. But he acknowledged the damage caused by the sex abuse scandal that has rocked the Roman Catholic Church.

Speaking at a formal welcoming ceremony at President Christian Wullf's Bellevue palace Thursday, the pope warned of society's growing indifference to religion. Earlier on his flight from Rome, the pontiff said he understood the increasing number of Germans leaving the church because of reports of recent sexual abuse involving priests. But he asked for patience, saying the church is “a net of the Lord that catches both good fish and bad.”

Chancellor Angela Merkel and President Wullf greeted the Bavarian-born pontiff upon his arrival at Berlin's Tegel airport at the start of his four-day visit. A small group of protestors carrying banners about sexism, homophobia and anti-Semitism was gathered just outside the airport.

The pope also met with Chancellor Merkel, with the two discussing the euro crisis and turmoil on the financial markets.

Later Thursday, Pope Benedict is scheduled to speak before the lower house of parliament, where as many as 100 lawmakers say they plan to boycott the pontiff's address. Interior Minister Hans-Peter Friedrich, a Protestant, criticized those who plan to boycott the speech for “arrogance, narrow-mindedness and provincialism.”

As many as 20,000 people are expected to demonstrate outside of parliament. Those expected at the demonstration include gay and lesbian rights organizations and groups that want to see reform in the church — on issues including divorce, ordination of women priests, abolishing celibacy for clergy, and support for victims of sexual abuse by priests.

Tens of thousands of Catholic faithful were expected to attend an open-air Mass at Berlin's Olympic Stadium Thursday night. During his visit, the 84-year-old pontiff will also hold Mass in the cities of Erfurt and Freiburg.

Germany's 50 million Christians are almost evenly divided between Protestants and Catholics, and many see the pope's visit as an opportunity to promote greater understanding between the two churches.