Krakow, Poland ? Spending a day steeped in nostalgia, Pope John Paul II visited one of the homes of his youth Saturday, stopped at his old university and consecrated a new basilica at a religious sanctuary where he often sought comfort during World War II.

“Many of my personal memories are connected with this place,” the Polish John Paul, 82, said at the end of a three-hour Mass he celebrated in a new basilica at the Sanctuary of Divine Mercy.

Pope John Paul II kisses 7-year-old Grzegorz Bielatowicz in front of the pope's former home in Krakow, Poland. Tens of thousands of adoring Poles gave the ailing pontiff a joyous welcome home Saturday.

“I used to come here, especially during the Nazi occupation, when I worked in the nearby Solvay” chemical plant and quarry, the pontiff recalled. “Every day I walked this road, coming to work … in wooden shoes that one used to wear in those days. How could one imagine that this man in wooden shoes would one day be consecrating the Basilica of Divine Mercy?”

In his ninth visit to his homeland since he became pope, John Paul is receiving a rapturous welcome from ordinary Poles and the nation’s top leadership. Former President Lech Walesa, a one-time shipyard worker who together with John Paul played a key role in undermining communism in Poland, explained in an interview after the Mass that John Paul is “the only authority, the only real unquestionable leader” of this country.

That image was reinforced when President Aleksander Kwasniewski and Prime Minister Leszek Miller met separately Saturday evening with John Paul. Both said afterward that they had discussed a wide range of Poland’s problems with him, including unemployment, faltering economic growth and the country’s bid to join the European Union.

“He’s in good shape, intellectually perfect,” Kwasniewski said after the talks. John Paul suffers from Parkinson’s disease, and his grueling schedule Saturday left him looking more tired than he had upon his arrival Friday evening, when he seemed invigorated to be home. The pontiff will celebrate an open-air Mass today and return Monday to Rome.

“I’m absolutely certain that this is not the last pilgrimage (to Poland), as some people think,” Miller said. “From the side of Polish authorities, there’s absolute readiness to have John Paul here as a guest whenever he wants to come. I gave the pope such a declaration, and he smiled and said, ‘Well, if God allows.'”

John Paul II expressed alarm Saturday at the swirl of conflict that has gripped the world since Sept. 11 and pleaded for an end to “injustice” underlying the turbulence.

“How greatly today’s world needs God’s mercy,” the pope said at the consecration of the church.

“Mankind,” John Paul said, “is experiencing bewilderment in the face of many manifestations of evil.

“Where hatred and the thirst for revenge dominate, where war brings suffering and death to the innocent, there the grace of mercy is needed in order to settle human minds and hearts and to bring about peace,” he said. “Mercy is needed in order to ensure that every injustice in the world will come to an end in the splendor of truth.”