Pope Francis, whose predecessors commissioned the Vatican's Sistine Chapel centuries ago, tried his hand at painting on Thursday when he put the final touches on a 3 km long mural while visiting a school west of Lisbon.
The mural is part of the "Life between Worlds" project by Scholas Occurrentes, an international educational movement that links about half a million schools on five continents. Francis is the group's main sponsor.
About 30 murals painted by students and community members were brought together to form a single work in the seaside town of Cascais.
The ceiling and walls of the room where the pope spoke to the students, and where the mural ends, were covered with painted themes such as human figures floating in the cosmos.
"You guys have painted your own Sistine Chapel," Francis said.
The 86-year-old pope was given an artist's paintbrush attached to a virtual reality gadget that allowed students at a school in Mozambique to see his brush strokes on a wall in their school in real time.
The first try did not go well. The pope, looking a bit bewildered, gave it a second try and managed to paint a green line in the shape of half of an elliptical arch.
"It's very virtual but not very physical," José María Del Corral, president of Scholas Occurrentes, joked between the pope's first and second attempts.
The real Sistine Chapel in the Vatican gets its name from Pope Sixtus IV, who had it built between 1473 and 1481. Michelangelo painted the ceiling for Pope Julius II between 1508 and 1512.
Francis, who is Lisbon for a global gathering of young Catholics, told the students at the school not to be afraid to take chances in life and to help downtrodden people.
"Sometimes in life, you have to get your hands dirty in order to keep your hearts clean," he told the students, who included non-Catholics and non-believers.
"Pray for me and those of you who do not know how to pray, send me good vibes," he said.
On Thursday evening the pope was due to address hundreds of thousands of young Catholics who have come to the Portuguese capital from around the world for the World Youth Day festivities.