Pope Benedict XVI encouraged prayers Friday for the beatification of his predecessor, Pope John Paul II — an eagerly awaited remark during his visit to Poland on a cause close to the hearts of many Poles.

Benedict has referred to the Polish-born John Paul as a great pope, "my beloved predecessor" and quoted from him extensively, but Poles were awaiting word on the beatification. Some even hoped that Benedict would announce it during his four-day visit.

The pope made his encouraging comments to a wildly enthusiastic crowd waiting beneath the front window of the Krakow archbishop's residence, from which John Paul made a custom of speaking to young people during his return visits as pontiff.

"I know that on the second day of every month, at the hour of my beloved predecessor's death, you come together to commemorate him and to pray for his elevation to the honor of the altars," Benedict said.

"This prayer supports those working on his cause, and enriches your hearts with every grace."

Immediately after John Paul's death on April 2, 2005, faithful started clamoring for quick sainthood for him.

Benedict announced last year that he had waived the traditional five-year waiting period for the beatification process to begin.

Church officials are investigating the case of a French nun who recovered from Parkinson's disease as a possible miracle, which is required for beatification, the last formal step before a person is considered for sainthood. A second miracle is needed for someone to be declared a saint.

Benedict earlier visited Czestochowa, following in John Paul's footsteps to the country's holiest shrine and urging Poles to cling to their faith.

On the second day of his tour of Poland, the German pope spoke frequently of John Paul, paying tribute to his efforts to bring down communism across Eastern Europe. But he also looked ahead, encouraging Poland to remain a strong Catholic voice on an increasingly secular continent.

"How can we not thank God for all that was accomplished in your native land and in the whole world during the pontificate of John Paul II," Benedict told an estimated 270,000 people who stood in a pouring rain during a morning Mass in a Warsaw square. It was there, during his historic 1979 visit, that John Paul inspired the Solidarity movement against communist rule.

In his homily, Benedict challenged moral relativism, or the view that there are no absolute values, and defended the church's unchanging traditional beliefs.

"Stand firm in your faith, hand it down to your children," Benedict said.

Authorities said some 250,000 people turned out at the Czestochowa shrine, home of the famous Black Madonna icon. John Paul, convinced the Madonna saved his life when he was shot by a Turkish gunman in St. Peter's Square in 1981, donated to the sanctuary the bloody sash he wore that day.

Addressing priests, nuns, seminarians and the faithful at the shrine, Benedict said "we must give great attention to the development of our faith, so that it truly pervades all our attitudes, thoughts, actions and intentions."

Shortly before the pope arrived by helicopter from Warsaw, a priest taught the crowd how to welcome the pope in German, emphasizing the words "Der Heilige Vater" — "The Holy Father." Benedict himself has refrained from speaking his native language, apparently because of sensibilities of elderly Poles who recall the brutal German occupation during World War II.

"I am very happy to sing for the pope," said 12-year-old Daniel Bubel, one of the red-shirted choirboys practicing for his arrival. "I would very much like to see him."

At the Warsaw Mass, Benedict warned the faithful against those "seeking to falsify the Word of Christ and to remove from the Gospel those truths which in their view are too uncomfortable for modern man."

"They try to give the impression that everything is relative: even the truths of faith would depend on the historical situation and human evaluation," he said, in remarks that echoed his homily at John Paul's funeral last year. "Yet the church cannot silence the spirit of truth."

The choice of site — called Victory Square in 1979 and today Pilsudski Square — recalled John Paul's challenge to "renew the face of the Earth, of this land" during his triumphant first trip to his native land after being elected pope.

That visit challenged the atheist authorities and is credited by Solidarity founder Lech Walesa with inspiring trade union resistance to Soviet-backed communist rule, which collapsed in 1989-90.

Spectators stood resolutely Friday in ponchos and under umbrellas, filling vast Pilsudski Square before an 82-foot metal cross.

Aneta Owczarek, 18, dripping wet without a raincoat, did not consider going indoors.

"No way," she said. "This is one of the most important events that could ever happen in Poland and we don't know if we'll ever see the pope here again."

Warsaw authorities said doctors treated about 100 people during the Mass, and 19 people were taken to hospital with cold or circulation difficulties, but there were no serious injuries.

The numbers were smaller than in 1979, when some 300,000 people filled the square, and 750,000 were in the surrounding streets. Police spokesman Pawel Biedziak provided the estimate of Friday's crowd, with a packed square but virtually abandoned sidestreets.

White and yellow Vatican flags decorated lampposts, and Benedict's picture stood in apartment windows; one window on Mazowiecka Street had pictures of both Benedict and John Paul.

"Today, the feeling is more spontaneous — in 1979, we still were under a different system, we were under a regime and people came because they wanted this meeting with the pope to bring fruit, and it did," said Barbara Kamela, 60, a retired bookkeeper who attended the 1979 Mass.

"John Paul II was dearer to us, because he was our brother," she said. "This pope is visibly trying to be close to us, we have a strong impression from him and I came to this Mass to be near him."

Benedict's four-day trip will include a stop at the Auschwitz-Birkenau death camp, a visit heavy with significance for Catholic-Jewish relations, a favorite cause of both Benedict and John Paul.