First, redirect people back to Christ. The reason for gossip is because they are believing a lie about God and themselves. Remember, Satan was the first gossiper when he talked trash about God. Show them how Jesus died for their sins, even the sins committed post-conversion. This sin should be a magnet to draw them back to the person and work of Christ for repentance, forgiveness and refreshing. (In this it should be noted that their issue is not just with another person but Christ. Jesus is Lord of the church; and so they are sinning against him.)
Second, redirect people back to the person. If they have an issue with someone, they should go and talk to them. If they have done some damage to the person’s character, then they should go and tell the person in humility and ask for their forgiveness. I will often tell the person that I will follow up with them in a week or so to see how the conversation went.
Third, they should also go in humility to the other people they have gossiped to. This closes the loop and reinforces the need to reject the sin of gossip. It reminds, or perhaps educates, those who have been exposed to this sin of the nature and danger of it.
Gossip is nasty. It is never good and should be despised by all who love Christ and his church. Instead of being passive and tolerating something that is widespread, we should be vigilant to remove something that is destructive and vile. Let’s step our game up and, starting with ourselves, work to shut down gossip.