Jim Cymbala, pastor of Brooklyn Tabernacle charges all the new members of the church to deal with the sin of slander. It doesn't matter if they hear slander or are involved with it themselves. They are to put a stop to it.
Why? Because slander can render a church ineffective.
He says this of slander in the church: "I know what most easily destroys churches. It is not crack cocaine, government oppression, or even lack of funds. Rather it is gossip and slander that grieves the Holy Spirit."
Ephesians 4.29 commands us: Do not let any unwholesome talk come out of your mouths, but only what is helpful for building others up according to their needs, that it may benefit those who listen.
When slander is on its way out of the church and encouraging words are the increasing norm, then the church will more and more reflect the image and heart of the Lord Jesus