"I didn't want to be pope," Francis said in response to a question from a student at a Jesuit school, ANSA reported.
"God does not bless a person who wants to be the pope," he said.
He called on Catholics to be active in politics.
"We Christians cannot play the part of Pontius Pilate and wash our hands," the pope said.
"We have to get involved in politics because politics is one of the highest forms of charity because it seeks the common good. Lay Christians have to work in politics."
Asked about the world economic crisis, Francis complained to the students that money had made slaves of people.
"Today the person is a slave and we have to free ourselves of these economic and social structures that make us slaves," he said.
"Today the person does not count, what counts is money. Jesus gave us the world, all of creation, to man and woman so that they would take it forward, not money."