There is no doubt that it lends itself to elucidating my shortcomings with respect to the things that come out of my mouth. And the result of shedding light on this causes me to feel guilty about the things I have said to others or about others. And my natural reaction is to clean it up -- in my own power and with my own resolve. If I can somehow, in my own flesh, bring my tongue under control, then I will be acceptable to God and will prove that I am accepted in God's Kingdom and that His life is flowing through me.
But what does James say in verse 8? "No human being can tame the tongue." So why am I trying to do it in my own flesh -- with my own effort alone? Verses 11 and 12 provide further proof. Blessing and cursing cannot proceed from the same source. The solution is not to try to clean up the evil source. The solution is to choose the correct source.
I cannot, of my own volition, clean up my tongue. I can, however, cry out to Jesus, who is my source, and ask Him to let His life and His words flow out through me. In reading the book of John we find that Jesus lived his life exactly in this mode. He only did and said what the Father told Him to do and say. So now that we have established the proper response to this passage, we can accurately and correctly delve into the nuances of how it affects our behavior.
The first reaction we might have is to stop saying four letter words. Or as we said in the South where I grew up, "Stop cussin'". Cursing goes much deeper than this. James is referring to words of denigration of any kind against those around us, including our family. There are plenty of us who may have cleaned up our vernacular, yet slander those around us or berate them with nicknames. Such verbal attacks, either in their presence or not, is a tool of Satan to destroy them. We must cry out to Jesus to be our source of words. Ask Him today to speak only His words as we interact with our family, our friends, and our coworkers.