During his sermon, Francis compared talking about people behind their backs to murder, Italy's ANSA news agency reported.
"Those in a community who talk about brothers, members of the community, they want to kill," the pope said.
"Where there is God, there is no hate, envy or jealousy," Francis said. "Nor are there those who want to kill with gossip."
'How to Train Your Dragon 2' releases 5-minute clip
Moore to attend retreat in to avoid Kutcher's wedding