ROME — The pope’s doctors did not think he was going to make it.

“It’s terrible,” Pope Francis gasped during a breathing crisis last month. The pope, his hand bruised with needle pricks and his oxygen saturation dipping to a dangerously low 78 during his long hospitalization, acknowledged in a failing voice that he might die. He held his doctor’s hand.

Francis had ruled out intubation, which would mean being kept unconscious, the leader of the medical team, Dr. Sergio Alfieri, said in an interview. So his doctors decided to treat the pneumonia in both his lungs with a last-ditch barrage of drugs that risked damaging his organs.

The pope’s closest aides had tears in their eyes as doctors asked the pope’s personal nurse, empowered to make life-or-death decisions, for permission to go ahead with more aggressive treatment. He consented, and, ultimately, the pope responded positively.

Even so, the worst had not yet passed. Less than a week later, Francis regurgitated some food and started choking. The doctors, fearing he might die on the spot, immediately suctioned his airway but worried that the inhalation would aggravate his deeply infected lungs. His chief doctor worried all was lost.

But it was not.

On Sunday, 38 days after he entered the Agostino Gemelli hospital, Alfieri discharged the leader of the Roman Catholic Church to return to the Vatican. He implored his patient, who had resisted going to the hospital in the first place, to rest and convalesce so as not to waste the chance he had been given.

“It was a miracle that he left the hospital,” said Alfieri, adding that the pope was now “not in danger.”

But when Francis made a brief appearance over the weekend, the public received a sobering glimpse of the toll the health crisis had taken on the 88-year-old pope. Greeting well-wishers from a hospital balcony, his voice was so weak it bordered on inaudible, his breathing so strained it sometimes looked like he gasped for air.

“You can see the decline,” Carlos Aguirre, a pilgrim from Colorado Springs, Colorado, said as he watched Francis struggle to speak.

Francis’ doctor said the pope agreed to a two-month convalescence that would put him on the road to full recovery. But prelates close to Francis are guarding against the possibility that his frail state is really the new normal. They have depicted his physical weakness as a powerful teaching moment about human dignity and argued that his evident lack of energy has no bearing on his authority.

Over the next two months, Francis will be less visible, harder to hear, more cloistered and more likely to stick to the script. The constraints, Vatican experts and officials say, will be a challenge for Francis, who, over the last dozen years, made far-flung travel, physical closeness to his flock, dramatic gestures and a freewheeling style the hallmarks of his pontificate.

Those touchstones of Francis’ papacy will now be on hold. The Vatican said Thursday that the pope’s participation in Easter rites in a special Jubilee year is uncertain.

Buckingham Palace announced that King Charles III had postponed a Vatican visit, “as medical advice has now suggested that Pope Francis would benefit from an extended period of rest and recuperation.” A papal schedule once packed with appearances has given way to written statements and remarks.

“Nothing will be as scintillating as it was before,” Alberto Melloni, a church historian and the director of the John XXIII Foundation for Religious Sciences in Bologna, said.

Alfieri said he instructed the pope to keep to his Vatican residence, which would be outfitted with oxygen but no other special equipment, and Francis agreed. He implored the pope to avoid large groups and especially exposure to small children, for fear of new infection.