A few years ago (or maybe it was several years ago; at this point of my life I have trouble knowing the difference), I got involved in an online discussion about whether Jesus ever swore.
You know...foul language...four-letter words...cussing.
I stood firmly in the camp that said, "No way! 'Let no unwholesome word come out of your mouth' and all that."
The opposing view argued that Jesus, while being the Son of God, was also fully human, dealing with people who didn't understand him. So of course, they thought, he used gritty language to express himself or vent his emotions.
Inherent in this line of reasoning was the belief that "dirty words" are not a sin anyway. That, of course, led to a completely different tangent that left me a little deflated because, after all, I cannot explain why certain words are on The Naughty List while other words, referring to the exact same bodily functions (or whatever), are perfectly acceptable in polite society.
The good news is that we don't need to solve that riddle right now, because I don't think that's what James is talking about in this verse anyway. Take a look at how he expands on the thought two chapters later:
We all make many mistakes. For if we could control our tongues, we would be perfect and could also control ourselves in every other way. We can make a large horse go wherever we want by means of a small bit in its mouth. And a small rudder makes a huge ship turn wherever the pilot chooses to go, even though the winds are strong. In the same way, the tongue is a small thing that makes grand speeches.
But a tiny spark can set a great forest on fire. And among all the parts of the body, the tongue is a flame of fire. It is a whole world of wickedness, corrupting your entire body. It can set your whole life on fire, for it is set on fire by hell itself.
People can tame all kinds of animals, birds, reptiles, and fish, but no one can tame the tongue. It is restless and evil, full of deadly poison. Sometimes it praises our Lord and Father, and sometimes it curses those who have been made in the image of God. And so blessing and cursing come pouring out of the same mouth. Surely, my brothers and sisters, this is not right! (James 3:2-10 NLT)
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Truth is...It is not so much our word choice, but the intended result of our words that reveals our character and the extent to which we are allowing the Holy Spirit to affect our human nature.

