TORONTO, July 28 — Speaking to a public audience about the child sexual abuse crisis for the first time since it engulfed the Roman Catholic Church this year, Pope John Paul II called the crimes and misdeeds of some priests a source of shame today and urged young Catholics not to lose faith.
"If you love Jesus, love the church," the Pope said during a homily at an outdoor Mass here this morning that was attended by hundreds of thousands of Catholics, many of them teenagers. "Do not be discouraged by the sins and failings of some of her members.
"The harm done by some priests and religious to the young and vulnerable fills us all with a deep sense of sadness and shame," the Pope continued, speaking in English.
"But," he added, his voice rising as he stressed that word, "think of the vast majority of dedicated and generous priests and religious whose only wish is to serve and do good."
Midway through that sentence, the pope was interrupted by applause from the crowd, which stretched out across the grass of an airfield that had been converted into a gargantuan outdoor cathedral.
He paused for the full duration of that ovation, a counterpoint to the firestorm of criticism this year about sexually abusive priests and the way Roman Catholic leaders have dealt with them.
His remarks were striking in several ways. The word shame represented stronger, more personal language than the pope had used this year about sexual abuse by priests.
Equally significant were the context and setting of the pope's brief discussion of the issue.
Several times during the past seven months, as the issue drew heightened scrutiny in several countries and plunged the Catholic Church in the United States into crisis, comments that the pope had written or made privately in Rome were distributed publicly.
In one of those, a pre-Easter letter to priests, he lamented that "a dark shadow of suspicion" had been cast over all priests by "some of our brothers who have betrayed the grace of ordination."
But today was the first time during that period that the pope actually spoke about the issue to a large public audience — one that included many thousands of people the same age as, or just a few years older than, the victims of the priests to whom he briefly referred.
He was appearing at the climactic event of the church's World Youth Day, a weeklong, international jubilee that celebrates the place of young people in the church. On Monday, the pope is scheduled to fly to Guatemala and then to Mexico as he continues an 11-day foreign trip.
Although his words conveyed sorrow, they also contained, and were delivered with, a measure of defiance. He focused as much on the good deeds of a majority of priests as on the bad deeds of a minority.
"There are many priests, seminarians and consecrated persons here today — be close to them and support them," he told his audience.
"And if, in the depths of your hearts, you feel the same call to the priesthood or consecrated life, do not be afraid to follow Christ on the royal road of the cross," he added, seemingly making a direct appeal for vocations. Some Catholic leaders fear that all the attention to sexual abuse by priests could make it more difficult than it already is to recruit young men into the priesthood.
The pope stopped well short of any assertion that a lack of vigilance among church leaders had contributed to the sexual abuse of children, as the details of some cases suggest and as many outraged American Catholics contend.
He also did not talk about how the church would try to protect children, although he had previously touched on that theme, as well as the culpability of church leaders, this year.
Those omissions disappointed advocates for victims of sexual abuse by priests.
"One the one hand, anytime anybody talks about this issue, someone benefits, so I'm glad he mentioned it," said David Clohessy, the national director of the Survivors Network of those Abused by Priests, an American group.
But, Mr. Clohessy added, "He took the easy route and talked about abusive priests and not about complicit bishops. The scandal has reached these proportions, these horrific proportions, not because of individual priests, but because of the bishops themselves, their continual recycling of, and covering for, the molesters."
Cardinal Theodore E. McCarrick of Washington, who was here for the Mass, said that a discussion of church leaders' conduct would not have been appropriate because the pope was delivering a message of hope to young Catholics. What was important, he said, was that the pope "let people know that he knew what was going on, that the church doesn't have its head in the ground."
Referring to the pope's use of the word shame, Cardinal McCarrick said, "It hits him very personally — that priests have not been able to live the life that he knows that they should live."
Several people in the crowd said that the pope had struck the right tone and that they were grateful.
"You don't throw the church out with a couple of bad apples," said Sean Hayes, 38, of Pickering, Ontario. When the pope began his comments on sexual abuse, Mr. Hayes said to a group of teenagers he was supervising: "Listen. Listen."
After the pope finished, several teenagers from Cleveland, Ohio, said it was important for the pope to acknowledge the sexual abuse problem, because it had upset so many Catholic children. "It can't be ignored," said Melanie Galizio, 16.
Last month, American bishops and cardinals drafted a new nationwide policy for dealing with sexually abusive priests and subsequently sent portions of it to Rome for approval. The Vatican has not responded.
Many worshipers attending the Mass had slept outdoors overnight to ensure places near the makeshift altar, crowned by a yellow cross as tall as a skyscraper, and they braved a driving rain this morning that turned their campground to mud.
The miserable weather yielded memorable images, like cardinals and bishops using one hand to lift their white robes above puddles and the other to clutch umbrellas.
Just a few minutes before the pope's remarks, the rain stopped and the sun appeared. The ailing pope spoke in a voice as emphatic and crisp as it had been in months, and at times with humor. "You are young and the pope is old — 82," he said. "It's not the same thing as 22 or 23."
He seemed to hit a valedictory note when he said, "Although I have lived through much darkness, under harsh totalitarian regimes, I have seen enough evidence to be unshakably convinced that no difficulty, no fear is so great that it can completely suffocate the hope that springs eternal in the hearts of the young.
"Do not let that hope die."