The Holy Spirit cannot move fruitfully among discord. He will not bless. Some people want to be blessed, but they don't want to change. God is watching His children constantly. He is displeased with the evil and is pleased with the good.
Gentle words cause life and health Harsh words cause discouragement and discord.
If it comes to that, remember that a good tongue is healing to sin-sick souls by convincing them of the wrong. This is a tool that The Holy Spirit uses as opposed to hateful and harsh words. Gentle words also reconcile people who are at varience. An evil tongue is wounding. It does not reconcile, which is God's Will, it only makes the situation worse.