Pope Francis made a stirring return to public life Sunday, surprising worshippers in St. Peter’s Square during a special Jubilee Mass for the sick and health workers – his first Vatican appearance since a life-threatening bout with pneumonia.

The crowd rose in applause as the pontiff, unannounced, was wheeled to the front of the altar. Cries of “I see the pope!” echoed as his image appeared on a large screen, showing him entering through the Holy Door before descending a ramp to the altar.

“Good Sunday to everyone,” Francis said, tapping the microphone before his voice – noticeably stronger than when he left the hospital March 23 – rang out. “Thank you very much.”

He wore nasal tubes to receive supplemental oxygen, which the Vatican said is being gradually reduced.

As he waved and blessed the crowd, his arm movements remained limited – a condition his doctor said was not related to his illness but to an unspecified injury suffered before his Feb. 14 hospitalization.

After the Mass, the pontiff greeted some of those who assisted in the service, many of whom bowed to kiss his hands. He exited the square through the Holy Door.

Francis has completed two weeks of what doctors say will be at least two months of prescribed rest. He continues to undergo physical, respiratory and speech therapy, as well as treatment for a lingering lung infection.

The pope referred to his recent illness in both his traditional Sunday blessing and the homily, which was read by Archbishop Rino Fisichella, the organizer of the Holy Year that is expected to draw some 30 million pilgrims to Rome.

Addressing the sick in the crowd, Francis said in the homily: “In this moment of my life, I share a lot: the experience of infirmity, feeling weak, depending on others for many things, needing support.

“It is not easy, but it is a school in which we learn every day to love and to let ourselves be loved – without demanding and without rejecting, without regretting, without despairing – grateful to God and to our brothers for the good that we receive, trusting for what is still to come.”

He also urged the faithful not to push the frail to the margins, “as unfortunately a certain mentality does today. Let’s not ostracize pain from our surroundings. Let’s instead make it an opportunity to grow together, to cultivate hope.”

In his Sunday blessing, Francis offered prayers for doctors, nurses and health care workers, “who are not always helped to work in adequate conditions, and at times are the victims of aggression. Their mission is not easy and must be supported and respected.”

The faithful were moved by the pope’s unexpected appearance.

“It was beautiful, something completely unexpected because I didn’t think I would see the pope,” said Pasquale Citrolo, from Trapani, Sicily. “Instead, he gave us this gift.”

Linda Elezi, from the Adriatic coastal province of Ancona, said she was touched by the pope’s surprise.

“We pray for him every day, and he prays for us and for peace and for all the world, because that is the message of our pilgrimage today: bring peace to all the world,” she said.

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