How we speak is of great importance because "death and life are in the power of the tongue" (Proverbs 21:18). Jesus even says, "whoever insults his brother will be liable to the council; and whoever says, ‘You fool!’ will be liable to the hell of fire" (Matthew 5:22). Again He says, "I tell you, on the day of judgment people will give account for every careless word they speak" (Matthew 12:36). Either Jesus is being too severe, or we do not have an accurate view of the power of words. The later must be true. In Ephesians 4:29, Paul says our speaking needs to 1) build others up, not corrupt, 2) fit the right occasion, and 3) give grace to those who hear.
One way we can be properly motivated to speak graciously to others is to see how God graciously speaks to us whose faith is in Jesus. Even though we have all sinned and spoken in ways that deserve "the hell of fire," Jesus came and died to call us forgiven, beloved child, and loved. We know His words are not empty; they are not flattery. Jesus' words of grace to you are as real as the scars on His hands.