For every kind of beast and bird, of reptile and sea creature, can be tamed and has been tamed by mankind, but no human being can tame the tongue. It is a restless evil, full of deadly poison. With it we bless our Lord and Father, and with it we curse people who are made in the likeness of God. From the same mouth come blessing and cursing. My brothers, these things ought not to be so.—James 3:7–10
Speaking is one of the most important things people do. With words we promise, inform, direct, comfort, persuade, and correct. Without words, expressing love and hate is practically impossible. Through speech we display our love, show our desires, picture our hopes, and voice our worries. Through words, people hear that which we believe is most important.
Some ways of talking come easy. Condemning, tearing down, accusing, criticizing—these things are natural. It is natural for us to know what is right and how people fail. It is natural to point out flaws. It is natural to remind people that they have flaws, that they sin, that they are sinners.
The gospel is unnatural, contrary to our normal ways of speaking. In this life people expect justice. Evil deserves to be punished, but through the gospel we forgive sinners. This is unnatural. The gospel is a word of mercy. It is hope to those without hope. It is life to those who deserve death. It is a foolish message about Jesus dying on a cross for the sins of others so that sinners could be counted as righteous in God's sight through faith alone.
The gospel gives eternal life to the unworthy. The gospel declares that God justifies the wicked, that he turns rebels into children. The worst kind of people—murderers, rapists, and adulterers—will be in heaven because Christ died for them. This is mercy.
Speaking the gospel is a uniquely Christian way of talking. Speaking the gospel is at the core of what it means to be a Christian:
Put on then, as God's chosen ones, holy and beloved, compassionate hearts, kindness, humility, meekness, and patience, bearing with one another and, if one has a complaint against another, forgiving each other; as the Lord has forgiven you, so you also must forgive. And above all these put on love, which binds everything together in perfect harmony. And let the peace of Christ rule in your hearts, to which indeed you were called in one body. And be thankful. Let the word of Christ dwell in you richly, teaching and admonishing one another in all wisdom, singing psalms and hymns and spiritual songs, with thankfulness in your hearts to God. (Col. 3:12-16)
It takes daily reading, thinking, memorizing, singing, and disciplined speaking to become good at speaking the gospel.