As John Boehner stood next to Pope Francis on the porch of the U.S. Capitol on Thursday, the House Speaker's contorted, tear-covered face suggested something more than his usual emotion.

A day later, it was clear what may have been weighing on his mind in that moment during an otherwise a career-capping triumph for the devout Roman Catholic who was hosting the pontiff on his visit to Congress.

Boehner abruptly announced his resignation on Friday, stunning Washington after a series of bitter battles with the many hardline members of his party determined to drive the Ohio Republican out of power.

Boehner had been almost wistful when he welcomed the pope to the Capitol and the pontiff remarked through an interpreter that Boehner's green tie was "the color of hope."

"I need a lot of hope today," Boehner replied.

Pressure had built on Boehner for months, with his critics complaining that he was not standing up forcefully enough to Democratic President Barack Obama.

Boehner thought of resigning as far back as last year, aides said, but changed his mind after his former No. 2, then-House Majority Leader Eric Cantor, lost in an upset primary election to David Brat, who was backed by the Tea Party movement.

On July 28, Representative Mark Meadows proposed a motion to "vacate the chair," which would have forced a vote on a new speaker. The next day, Boehner brushed off the call for his ouster, saying it was "no big deal" because he had broad support among Republicans who control a majority in the chamber.

More recently, conservative House members warned they would watch closely as Boehner dealt with a dispute over keeping the government funded after the Sept. 30 end of the fiscal year. They said they would reject any funding plan that failed to cut off support for women's healthcare group Planned Parenthood.

Boehner met with conservative Republicans late on Thursday afternoon to discuss the stand-off.

Afterward, Representative Mick Mulvaney was asked if there had been discussion of unseating Boehner. He said he could not address it, but any member could move that at any time.

Boehner said he discussed resigning with his chief of staff later that day. "My chief of staff and I talked late yesterday. I had told him I was thinking, today might be the day. And I told him I'd sleep on it," Boehner said at a news conference where he walked to the podium singing, "What a wonderful day."

Before going to sleep that night, he said he told his wife his mind was nearly made up. Her reaction? "Good," Boehner said.

"Last night I started thinking about this. I woke up. I said my prayers, as I always do, and decided today was the day I'll do that. Simple as that."