Pope Francis led the Angelus prayers at the Vatican just days after undergoing a hernia operation.
He expressed his gratitude to those who sent him messages of support while he was convalescing in the hospital.
The 86-year-old Pope has suffered from a series of health issues since his election in 2013.
He underwent a three-hour operation to remove a painful hernia and is now recovering.
During the prayer, Pope Francis
condemned the trawler sinking off Greece and the attack on a school in Uganda.
He urged efforts to prevent such tragedies from happening again.