Pope Francis is calling for a change in the culture of seminaries, saying priests who are taught only to toe the line will become "little monsters."
The pontiff expressed his vision for a more open and joyful religious education system during a three-hour talk with the heads of the orders in November, but his remarks were not published until now in the Jesuit journal Civilta Cattolica.
Taking another swipe at clericalism — a term often used to express a very formal, elitist attitude by some priests — Francis said seminaries and "houses of formation" need to keep up with the cultural times.
"Problems are not solved simply by forbidding doing this or that. Dialogue as well as confrontation are needed," he said.
"To avoid problems, in some houses of formation, young people grit their teeth, try not to make mistakes, follow the rules smiling a lot, just waiting for the day when they are told: 'Good, you have finished formation.' This is hypocrisy that is the result of clericalism which is one of the worst evils.
"Formation [of future priests] is a work of art, not a police action," he added. "We must form their hearts. Otherwise we are creating little monsters. And then these little monsters mold the people of God. This really gives me goose bumps."
In the 10 months since he was elected leader of the Roman Catholic Church, Francis has become known for his plain-spoken, sometimes blunt style — and it was on full display in this interview.
"Just think of the religious who have hearts as sour as vinegar," he said at one point. "They are not made for the people. In the end, we must not form administrators, managers — but fathers, brothers, traveling companions."
Francis, who was named Time magazine's person of the year for 2013, said men should run toward the priesthood, not away from secular life.
"The ghost to fight against is the image of religious life understood as an escape or hiding place in face of an 'external' difficult and complex world," he said.
Echoing past comments, the former archbishop of Buenos Aires called for priests to work directly with the poor and other on the fringes of society.
"This is really very important to me: the need to become acquainted with reality by experience, to spend time walking on the periphery in order really to become acquainted with the reality and life-experiences of people," he said.
"If this does not happen we then run the risk of being abstract ideologists or fundamentalists, which is not healthy."