When the newly elected Pope Francis told the cardinals at dinner that he needed to call in to his accommodation to pick up his bags and pay the bill, they thought it was a joke.
But when a dark car pulled up outside a drab grey building with graffiti on the walls where visiting priests stay while in Rome, it was clear he had been serious.
The new spiritual leader of the Catholic Church's 1.2 billion followers stayed in the hostel last week during discussions ahead of the conclave and left his belongings there.
Yesterday morning he turned up unannounced to retrieve his bags and insisted on paying the bill, saying he wanted to set an example.
It was just one of a series of spontaneous acts in the Pope's first 24 hours in office that left his minders struggling to keep up.
"We are going to have to get used to a different way of doing things," said Fr Thomas Rosica, a Vatican spokesman.
The speed of the election on Wednesday convinced commentators that an Italian had been chosen, prompting the bishops to issue a formal statement welcoming Cardinal Angelo Scola, the apparent front-runner. But inside the Sistine Chapel, the cardinals were instead paying homage to the 76-year-old Argentine, who stood to greet each of them, declining to sit on a throne.
As the cardinals left to go for dinner, the new Pope walked past the papal car, with its Vatican City 1 registration, and boarded a bus with the others.
Over dinner he gave a short speech to those who had elected him, remarking: "May God forgive you for what you have done."
Yesterday, he set off through Rome at 8am in a plain car without a cavalcade for an unscheduled visit to the Basilica of Santa Maria Maggiore to pray, taking the clergy and a group of schoolchildren by surprise.
Meanwhile, the childhood sweetheart of Pope Francis yesterday revealed that she had been forced to reject his boyhood offer of marriage, a move which eventually led him to devote his life to God.
The woman, known only as Amalia, said that the young Jorge Mario Bergoglio, when they wore both just 12 years old in the Buenos Aires suburb of Flores, declared: "If I can't marry you, I'll become a priest."
She spoke as the only remaining sibling of the new Pontiff confided in her that he never wanted to become the leader of the world's 1.2 billion Catholics.
Maria Elena Bergoglio, 12 years the junior of the 76-year-old Pontiff, said he never wanted to be pope and now faced a lifetime of "infinite loneliness".
"He didn't want to be pope and when we chatted privately about it, we joked at the prospect and he would say 'no, please no'."
"But I am also totally proud that he is the new Pope – because he's the first from outside Europe, because he's Latin American, he's Argentina and he"s my brother."
From what she had seen of his own reaction to the news on television, he also seemed pleased, she said. "The expression on his face spoke of a fullness of heart," she said.
Ms Bergoglio said that she never knew anything about his young love life.
However yesterday, speaking from her home in Flores, an emotional Amalia said that the "romance" did not prosper because of the opposition of her parents.
"When we were young, he wrote me a letter and I didn't reply to him. What I wanted was for him to disappear from the map. I never saw him after that – my parents kept me away from him and did everything possible to separate us."