Pope Francis says that overly pious priests scare him, and he tries to stay clear of them as much as possible.

According to Raw Story, the well-loved pope said on Friday during a conference on training for the priesthood that he is instinctively suspicious of priests who are hypocritical of their own religiousness.

"I will tell you sincerely, I'm scared of rigid priests," the 78-year-old pope jokingly said. "I keep away from them. They bite!"

Pope Francis used humour to convey his message concerning a serious matter. A lot of unstable individuals seek out a clerical career, he explained, and unless they are weeded out properly by the church, the faithful will suffer.

This is why the pope strongly suggests that seminaries should always assess not just the spiritual state of candidates but also their physical and psychological condition. "There are often young men who are psychologically unstable without knowing it and who look for strong structures to support them. For some it is the police or the army but for others it is the clergy," the pope said.

He warned that these disorders only manifest at a later date, so it will not be easy to spot it from the get-go.

However, the pope said he personally finds it worrisome when a priest takes pride in being extremely devout.

"When a youngster is too rigid, too fundamentalist, I don't feel confident (about him). Behind it there is something he himself does not understand. Keep your eyes open!"

"If you are sick, if you are neurotic, go and see a doctor, spiritual or physical," Pope Francis then suggested to those who might be unfit to join the church. "The doctor will give you pills. But, please, don't let the faithful pay for neurotic priests."