Pope Francis, who has raised the possibility of retirement for reasons of poor health, praised the humility of a 13th-century Pope who was one of the few in history to resign rather than rule for life.

The announcement of a visit by the head of the Roman Catholic Church to L’Aquila, in the central Apennine Mountains, sparked speculation of a possible resignation announcement after 20 new cardinals were appointed this weekend.

The city was largely destroyed by the 2009 earthquake that killed 305 people and is still being rebuilt. It is the burial place of Celestine V, who resigned as pope in 1294 after only five months to return to his life as a hermit.

In his homily during a mass for thousands of people in the town square, Francis noted that Dante had ridiculed Celestine’s Divine Comedy for his cowardice in abdicating his papal role, referring to the decision as the “Great Refusal.”

Francis, who has a painful knee problem and sciatica, arrived at the city’s cathedral to pray at Celestine’s grave in a wheelchair and helped him stand up. He said that by abdicating power, Celestine showed the power of humility.

“In the eyes of men, the humble are seen as weak and losers, but in reality they are the real winners because they are the only ones who fully trust the Lord and know His will,” the 85-year-old pope said.

“Humility consists not in an underestimation of oneself, but in a healthy realism that makes us aware of our potential as well as our misery,” Francis said. He praised Celestine’s courage because “no logic of force was able to imprison him or manage him.”

Francis’ predecessor, Benedict XVI, who in 2013 became the first pope in nearly 600 years to resign voluntarily, visited L’Aquila four years before stepping down. In the past, Francis also praised Benedict’s bravery.

Francis denied rumors that he plans to resign anytime soon himself, but also insisted that resignation should be an acceptable option for sons who feel they can no longer lead the world’s more than 1.3 billion Catholics.

He described how the helicopter that took him to L’Aquila on Sunday had to fly over the city in thick fog before finally finding a hole, saying it shows how people should take advantage of the “hole” when it presents itself.

Sixteen of the cardinals enlisted on Saturday will be eligible to attend a secret meeting of those who will be called to choose Francis’ successor – who according to Vatican rules must be under 80 at the time of voting – if he is to tender his resignation.

New cardinals come from all over the world including Brazil, Nigeria, Singapore and East Timor.

The instigations meant that Francis chose 83 out of 132 cardinals eligible to elect a new pope, nearly two-thirds of the total and to be exact the proportion required to pass any proposed name.