Why does James use a vapor or mist metaphor for human life (James 4:14)?
In order to warn us about the danger of planning for our future without regard for God’s will, James uses the metaphor of mist as a reminder of life’s brevity. If you are standing outside on a cold day, you are able to see your breath. Have you ever noticed how quickly the mist of your breath vanishes? James says that brief appearance of our breath is an image of human life—short, ephemeral, quickly appearing, and quickly vanishing.
Compared with eternity, human life is incredibly short. Therefore, we are arrogant and sinful when we make plans for the future of our very short lives without considering the Lord and His will for us.