WASHINGTON (CNS) -- With Pope Francis scheduled to address a joint meeting of Congress Sept. 24, political pundits speaking Feb. 8 to the Catholic Social Ministry Gathering said the event will be something new in Washington.

"He has a message which makes both sides uncomfortable," said Mark Shields, a syndicated columnist and frequent television and radio commentator. "It's going to be unlike any State of the Union address we've ever seen."

The address by Pope Francis will be the first time a pope has spoken to the joint assembly.

While it's not clear what the format of the event will be, Shields imagined the pope speaking from the podium in the House chamber, with Vice President Joe Biden, who serves as president of the Senate, and House Speaker John Boehner sitting behind him, as they do during the president's annual address to Congress. What Shields called the usual choreography of the State of the Union would have new wrinkles.

He imagined watching "Joe Biden and John Boehner, both Catholics, (but from different political parties, Democratic and Republican, respectively) figuring out when to stand and applaud."

Shields was joined by David Brooks, a columnist for The New York Times and contributor along with Shields on the PBS NewsHour.

The pair spoke to the annual gathering of people involved in Catholic social ministries. The Feb. 7-10 event includes workshops and speakers on a range of topics and preparation for lobbying members of Congress on key issues. About 550 people were registered for this year's gathering, which is co-sponsored by dozens of independent Catholic organizations and offices of the U.S. Conference of Catholic Bishops.

Brooks said one of the lessons Pope Francis brings to the halls of Congress is that he "personifies humility. There's not a lot of that here."

Shields said he thinks the pope's influence is showing in U.S. politics, particularly in the recent emphasis by President Barack Obama, Boehner, Sen. Marco Rubio, R-Florida, and former Massachusetts Gov. Mitt Romney in talking about the poor.

The pair also touched on a variety of other political topics and praised the work of the conference participants.