The devil’s mission is always to destroy, Pope Francis said Friday, but his worst assaults are not frontal attacks, but subtle, “well-mannered” persuasion.

In his homily at Mass in the Santa Marta residence Friday morning, the pope said that Satan is most dangerous when he presents himself as a friend who only wants to help us.

The pope was reflecting on the Gospel passage of the day Jesus speaks of a devil who has been cast out and later returns with seven other demons “more wicked than itself,” who set up residence in a person’s soul.

“Many times when Jesus drives out demons, they try to ruin the person, to do harm, even physically,” the pope said, because the devil never wants to leave.

“When he cannot destroy face to face — because there is a force of God that defends the person — the devil is smarter than a fox, he is astute, and seeks the way to regain possession of that house, of that soul, of that person,” he said.

When the demons enter and take up residence there, the condition of that man becomes worse than before, Francis noted, because before he was a possessed man — the demon was there and did not leave him alone — but now “he continues to be a possessed man, but without realizing it.”

“When the devil cannot impose himself by force, when he cannot destroy a person through clear vices, when he cannot destroy a people with wars and persecutions, he thinks up another strategy and, dear brothers and sisters, it is the strategy that he uses with all of us,” Francis said.

In the Gospels, Jesus often casts out demons, Francis noted. These demons “were his true enemies and our enemies,” he said, and the real struggle is the original combat “between God and the ancient serpent, between Jesus and the devil.”

“The devil’s mission is to destroy,” the pope said. “This is his vocation: to destroy the work of God.”

These are not “priests’ inventions,” Francis insisted, but the reality of spiritual warfare.

Every person faces this combat, the pope said, and we all should be aware of it.

“We are Christians, Catholics, we go to Mass, we pray: everything seems in order, yes, we have our faults, our little sins, but everything seems in order,” he said. And so the devil “plays” at being “well-mannered.”

“He goes, sees, looks for a nice bunch of friends, knocks on the door – ‘Excuse me. May I come in?’- he rings the doorbell and these polite demons are worse than the first, because you do not realize you have them at home.”

“This is the worldly spirit, the spirit of the world,” he said.

Demons can also destroy us “politely and diplomatically,” Francis said. “They do not make noise, they make friends, they persuade you — ‘No, come on, it is not too much, no, but up to here it is fine’ — and they take you on the path of mediocrity, making you lukewarm.”

“I tell you: I am more afraid of these demons than of the first,” Francis said. “And so when people tell me: ‘we need an exorcist because a person is possessed by the devil,’ I do not worry as much as when I see these people who have opened their door to well-mannered demons, the ones who persuade you they are not really enemies, but friends.”

“Because, as the Gospel says today, ‘the last condition of that man becomes worse than the first,’” he said.

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