Looking frail, Pope Francis made his first, brief, appearance in more than six weeks on Sunday, appearing on the balcony of a Rome hospital to greet hundreds of people gathered in the square in front.

“I see a woman with yellow flowers,” said Francis, who was brought out on the second-floor balcony in a wheelchair. “E’ brava,” he said in appreciation of the woman. Then he sat and waved with both hands while people cheered and waved flags.

The pope’s voice was frail and raspy, which was to be expected for a patient who had suffered serious damage to his lungs and respiratory muscles, as his doctors explained at a news conference Saturday.

People began cheering and rhythmically clapping: “Francesco.”

“Long live the pope,” someone called to more cheers. After a few more moments, the pope was wheeled back into the hospital.

Only weeks ago, there was great concern within the church and beyond that Francis might not recover from a bout of pneumonia he had suffered in both lungs and other respiratory infections. His doctors, speaking at a news conference at the Policlinico A. Gemelli hospital on Saturday evening, said that the pope’s pneumonia had been so severe that it had twice put his life in critical danger.

But the pope received drug therapy treatment and oxygen that resulted in a “slow and progressive improvement,” allowing him to overcome the most critical episodes, Dr. Sergio Alfieri, the leader of the medical team taking care of the pope, said Saturday.

As in the past six weeks, Francis did not impart the traditional Sunday Angelus blessing that he normally gives from the Apostolic Palace overlooking St. Peter’s Square.

Later on Sunday, Francis was expected to return to the Casa Santa Marta, the guesthouse in the Vatican where he lives, to convalesce for another two months. The doctors said Saturday that Francis should avoid unnecessary exertions as well as meeting with large groups and people with small children, to minimize coming into contact with potential sources of infection.

Dr. Luigi Carbone, Francis’s Vatican-based doctor, said the pope’s residence was sufficiently equipped to deal with his medical needs and had emergency services available for him around the clock.

Francis entered the hospital on Feb. 18 with an acute respiratory insufficiency from viral and bacterial infections. The pope, his doctors said on Saturday, had never been intubated and remained alert and conscious throughout his hospitalization.

Francis remained in critical condition for several weeks as he experienced an asthmatic respiratory crisis; initial, mild kidney failure; and a bronchial spasm that caused him to inhale his vomit after a coughing fit. He used noninvasive mechanical ventilation during the night and high-flow oxygen therapy during the day.

Doctors insisted that Francis, who had kept up a grueling schedule before his illness, needed to take it easy for at least two months.

“Convalescence is by definition a phase of recovery so it is clear that in the period of convalescence, he will not be able to carry out his daily activity of meeting with people as he was used to,” at least in for time being, said Dr. Carbone.