I've been looking for the word "gossip" in the Catechism of the Catholic Church. I can't find it there, even though I've used an advanced Google search technique (i.e., I used "site:")! I suspect it isn't used there because it's too imprecise and doesn't get specifically at an issue.
Pope Francis, has used the term a number of times in his homilies, however, and even used the expression "the terrorism of gossip".
But, what, precisely, is "gossip"? Dictionary.com's primary meaning (meaning #1) is "idle talk or rumor, especially about the personal or private affairs of others" and gives, by way of example, "the endless gossip about Hollywood stars." (A "rumor", by the way, is "a story or statement in general circulation without confirmation or certainty as to facts.")
The Church identifies detraction and calumny as sins against the 8th Commandment. In paragraph 2477, we find precisely what the issues are:
Respect for the reputation of persons forbids every attitude and word likely to cause them unjust injury. He becomes guilty
- of rash judgment who, even tacitly, assumes as true, without sufficient foundation, the moral fault of a neighbor;
- of detraction who, without objectively valid reason, discloses another's faults and failings to persons who did not know them;
- of calumny who, by remarks contrary to the truth, harms the reputation of others and gives occasion for false judgments concerning them.
So, as it happens, Pope Francis is right in speaking of "the terrorism of gossip", because it can destroy a person's good reputation and make their life a a living hell. The fact that it can descend to that level, however, does not mean that it always, or even usually, does. Gossip frequently demeans the subject of that gossip, because it entails focus on the faults of others (whether true - as in detraction - or made up/invented - as in calumny).
We human beings are chatters. Chatting is a way of passing the time and maintaining human contact, something akin to watering a plant. Chatting frequently turns to discussing others who are not present. Unfortunately, this can become an occasion of sin, if we are attracted to focusing on the faults of others. This can, and often does, happen while chatting if we have a tendency to judge others, to think something like "I may be imperfect, but I'm not like that!"
Thus, the Church points to two specific virtues to combat this problem: humility and respect. If we cultivate humility, we won't be so tempted to find excuses for our own behavior in the faults of others. If we cultivate respect for others, we won't be inclined to think ill of them.
Pope Francis points to the "terrorism of gossip", because, in its worst form, it involves ganging up on someone, to attack someone's reputation. It says: "This person is a sinner. We are the good people." It isolates them, leaving them without moral support. In effect, it excommunicates them. Like a plant without water, they can shrivel and die.
Yet, we are called to build communion, not destroy it. This is what it means to build the kingdom of God.