I think with this passage, James pretty much concludes his speech on how true faith expresses itself. And again, throughout his whole letter, he has focused on love, speech, and purity.
In these last few verses, I think he’s going back to the theme of purity and not becoming polluted by this world.
Part of that pollution is the love that people have for the things of this world. But part of that pollution is the arrogance that comes from having the things of this world. Here we see Christians who were pretty successful in the world, successful business people and merchants. And because they were so successful, they were starting to forget their need for God. They had forgotten that all that they had ultimately came from him.
And so James says,
Now listen, you who say, “Today or tomorrow we will go to this or that city, spend a year there, carry on business and make money.”
Why, you do not even know what will happen tomorrow. What is your life? You are a mist that appears for a little while and then vanishes. Instead you ought to say, “If it is the Lord’s will, we will live and do this or that.”
As it is, you boast and brag. All such boasting is evil. (13-16)
In a lot of ways, this is connected to verses 10-12.
In those verses, James asked, “Who are you that you think you have the right to judge your neighbor, to despise him by slandering him and treating him like dirt?”
Now he again asks, “Who do you think you are that you boast as you do? You’re nothing. You’re mere mist, here today and gone tomorrow. You don’t even control how much breath you have left in your life.”
So what do we get from all this? Put away your arrogance. Draw near to God and humble yourself before him.
And stop despising others. Rather, get back to what Jesus commanded and start loving your neighbor as yourself.”
James then concludes,
Anyone, then, who knows the good he ought to do, and doesn’t do it, sins. (17)
And so we come full circle to what James said earlier in chapter 2, that faith without works is dead. For if you are walking in arrogance, judging others with your mouth, neglecting the needs of those around you, and living in adultery with the world, do you really have faith? Or is your faith mere words, an empty shell.
What kind of faith do you have?