Ahh, James 3... a chapter that was written directly for me! (-: Controlling the tongue is so difficult for me; I have lots of strong opinions and of course I'm always right, right??
It's amazing, isn't it, how the tongue is such a powerful thing? We let is take over and control our lives. James says we let it "boast" and it's so true! Our tongue is what says it will do things, but it really is our other body parts that accomplish the task. For example, it is our tongue that might brag about how we can run a marathon, but it's our legs that actually do it! Hopefully we aren't the tongue in our own churches, boasting of things that we leave for others to do.
"But I tell you that men will have to give account of the day of judgement for every careless word they have spoken. For by your words you will be acquitted, and by your words you will be condemned." Matthew 12:36-37
The things we say are so powerful and they DO matter. Often I forget how much they matter. We can do great good or great harm with our words. We can build people up and we can tear them down. It's scary because I, and others, often don't realize the destructive power of the tongue. The things that fly out of our mouths without thought can never be retrieved.
But it's not just our words that matter. James says that if we are wise, we will show it in our good lives. However, if we (unwisely) have selfishness in our hearts, it will be manifest in our life. We can try to boast that we are wise, but our life will reveal otherwise.
Think about all the things James lists as aspects of wisdom: pure, peace-loving, considerate, submissive, merciful, fruitful, impartial, and sincere. These are usually not considered to be virtues in our society!! They are often belittled along with those who practice them. But God tells us to "sow in peace" to "raise a harvest of righteousness!"