Pope Francis, in a conversation with journalists on a plane bringing him back from a visit to Brazil, addressed some of the Church's more controversial issues.

Pope Francis surprised the Catholic faithful Monday by saying the Roman Catholic Church shouldn't marginalize gay priests, saying: "Who am I to judge?"

The comments followed one of the largest papal Masses in recent history over the weekend, when the pope told an estimated 3 million people on the Copacabana beach in Rio de Janeiro to spread the Gospel to "the fringes of society."

The newly appointed leader of the Roman Catholic Church then took to his papal airplane, where he told a group of reporters on the long flight back to Rome that gay Catholic priests "should not be marginalized" in the church.

"If a person is gay, seeks God and has good will, who am I to judge?" the pontiff reportedly said, in response to a question about a rumored "gay lobby" in the Vatican. He did denounce illegitimate influence on the church.

The comments prompted worldwide speculation about whether the pope, known as a staunch opponent of gay rights, was signaling a slightly softer tone or a more dramatic shift on a longstanding hot-button issue for the church.

The church teaches that homosexual acts are sinful, but simply being gay — if celibate — is not. It has also been a strong and vocal opponent of efforts to legalize same-sex marriages around the world, including in Maryland.

Under Pope Francis' predecessor, Pope Benedict XVI, gay men were to be blocked from becoming priests. Pope Benedict resigned in February.

The church is eager to bring Catholics back to the church, and reframing faith conversations away from denunciations and toward ideas like mercy is a strategy that the pope favors, said Chad C. Pecknold, an assistant professor of theology at the Catholic University of America in Washington who teaches on the papacy.

"The message of mercy, I think, is one he is sounding out on every single issue that the culture has identified as one it rejects the church's teachings on," Pecknold said. "What Francis wants to say is, 'Let's talk.' "

The pope offered his thoughts in a remarkably open news conference in response to questions about rumors of a "lobby" of gay priests seeking to influence the Vatican. He said he disapproved of any such lobby or influence, but distinguished influence-seekers from priests who might happen to be gay.

Pecknold said it was important to consider that context when reading the pope's comments, but he also said the pontiff would have been aware that his comments to international journalists about homosexuality would have been viewed in a broader context.

"We're going to hear this over and over and over again," Pecknold said. "The way in which Francis wants to initiate a conversation, the way in which he wants to invite a conversation, is through this message of mercy."

Sean Caine, a spokesman for Baltimore Archbishop William E. Lori, said the pope "spoke with compassion and understanding while at the same time reaffirming the teaching and practice of the Church."

According to a Pew Research Center poll analysis this year, there are about 75 million Catholics in the United States, which has the fourth-largest Catholic population in the world. The country with the largest is Brazil.

The Archdiocese of Baltimore includes about 500,000 Catholics.

Some saw more promise in the pope's message.

Francis DeBernardo, executive director of New Ways Ministry, a "gay-positive" Catholic ministry in Maryland, said he saw the pontiff's words as "a major departure" from his predecessors, even if they didn't mark a shift in the church's official stance on homosexuality.

"Official Catholicism talks about homosexuality in the language of sin and in the language of human dignity, and his predecessors have emphasized the language of sin," DeBernardo said. "What this shows is he wants to emphasize the language of dignity.

"That's a major step forward," DeBernardo said. "It's a step that we've been waiting for and hoping for for a long time."

Outside Baltimore's Basilica of the Assumption after a midday Mass on Monday, several churchgoers said they supported a more progressive stance on gays in the church.