A tearful Speaker John Boehner kicked off Wednesday’s House tribute to the victims of the Arizona shooting, calling for “strength” in what he described as “difficult hours for our country.”

The Ohio Republican’s remarks were part of the House consideration of a resolution condemning the violence and honoring those who were injured and killed. Members will devote six hours to the resolution.

“We are called here to mourn a despicable act of violence. … These are difficult hours for our country,” said Boehner, who was installed as Speaker one week ago.

“What this institution needs now is strength,” Boehner added, choking back tears. He acknowledged that Members and staff are enduring “a litany of unwanted emotions that no resolution could capture.”

“Today is not ceremony, but tragedy that stirs us to faithfully fulfill our oath of office,” he said.

The Republican leader paid special tribute to Rep. Gabrielle Giffords (D-Ariz.), who suffered a gunshot wound to the head, calling her a “public servant of the highest caliber.”

He also spoke of Giffords aide Gabe Zimmerman, who died at the scene. “This is the great cause for which Gabe gave his life,” Boehner said.

Minority Leader Nancy Pelosi also delivered an emotional tribute to the victims. “Words are inadequate at a time like this,” the California Democrat said. “Nevertheless, I hope it is a comfort … that so many people mourn.”

Speaking to the resolution, Pelosi urged her colleagues to “read it, pray over it and be grateful we have this great opportunity to comment on it.”

Minority Whip Steny Hoyer urged Members to temper their rhetoric in the wake of the attack.

“Let us speak to our neighbors in a spirit of unity. Not a false and shallow unity, not a unity that wishes away a difference,” the Maryland Democrat said, adding that, “There is perhaps nothing we can do to prevent the mindless violence of the few, but we can and must appeal to the best instincts of the many.”

“We will have the last word. God bless this House, God bless this Congress and God bless America,” Boehner said.