On what may well be his last official visit to his birthplace, Pope John Paul II urged the world to put an end to war and suffering around the world. It was an emotional sermon in Krakow, the city where he endured Nazi repression. The pope returned to his native Poland for the ninth time to spend four days in Krakow, where a forced laborer for Nazi German occupiers and where, as a priest, he resisted decades of communist rule.

At least 10,000 people prayed and sang as the frail, 82-year-old pontiff consecrated the newly completed Basilica of God's Mercy in Krakow.

As they sang, some believers waved banners reading "We love you, holy father." Most watched the pope on a giant television screen outside the packed basilica, which was built at a shrine on the site where he used to pray during World War Two.

The new church, shaped like a ship parting the waves, is dedicated to Saint Faustina, a mystic Polish nun who died in 1938 and who has special significance for the pope. He prayed at a church on this spot every day on his way to work in a soda plant commandeered by the Nazis.

The Solvay chemical factory is now a modern cinema complex and is seen as evidence of the changes in Poland over the 13 years since the switch from impoverishing communism to free-market democracy.

Krakow also became his residence as a cardinal, from where he helped lead the struggle against communism. He gave inspiration to the Solidarity movement, which grew out of John Paul's first return home as pope in 1979.

The pope is no longer the articulate, middle-aged man of the seventies and eighties. He suffers from Parkinson's disease which causes his speech to become slurred.

Although John Paul seemed breathless at times, he still managed to convey a message of hope and a call to fight injustice. He said that where hatred and the thirst for revenge dominate, where war brings suffering and death to the innocent, there the grace of mercy is needed.

The pope also referred to evil in the world, a clear reference to the September 11 terror attacks in the United States and their aftermath.

The election of the Polish pope and John Paul's own support for Solidarity, the first free trade union in the communist eastern bloc, helped bring about the undoing of the Soviet grip over eastern Europe, according to protagonists of the era, such as former Soviet president Mikhail Gorbachev.

The pope made no reference to reports that he may soon retire because of ill health. Still, despite his frailty, he is a hero to many Poles. Some 200,000 of them lined the streets to cheer John Paul as he traveled through Krakow to the Saint Faustina church. More than 10 times that number were expected to attend an open-air mass in Krakow's Blonie park on Sunday.