James 4:14

12 There is one lawgiver, who is able to save and to destroy: who art thou that judgest another?

13 Go to now, ye that say, To day or to morrow we will go into such a city, and continue there a year, and buy and sell, and get gain:

Whereas ye know not what shall be on the morrow. For what is your life? It is even a vapour, that appeareth for a little time, and then vanisheth away.

15 For that ye ought to say, If the Lord will, we shall live, and do this, or that.

16 But now ye rejoice in your boastings: all such rejoicing is evil.

Do read the surrounding verses too, because the context often says more than a single verse.

Compare

BSB
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.
KJV
Whereas ye know not what shall be on the morrow. For what is your life? It is even a vapour, that appeareth for a little time, and then vanisheth away.
WEB
Yet you don’t know what your life will be like tomorrow. For what is your life? For you are a vapor that appears for a little time and then vanishes away.
ASV
whereas ye know not what shall be on the morrow. What is your life? For ye are a vapor, that appeareth for a little time, and then vanisheth away.
DARBY
ye who do not know what will be on the morrow, ([for] what [is] your life? It is even a vapour, appearing for a little while, and then disappearing,)
BLB
who do not know what [is] of tomorrow. What [is] your⁺ life? For it is a vapor appearing for a little [while] and then vanishing.
ÅB
Dere som ikke vet hva som skal hende imorgen! For hva er deres liv? dere er jo en røyk som viser seg en liten stund og så blir borte!
OTB
Men dere vet ikke hvordan livet deres vil være i morgen. Dere er en tåke som viser seg en liten stund og så forsvinner.
B1930
I som ikke vet hvad som skal hende imorgen! For hvad er eders liv? I er jo en røk som viser sig en liten stund og så blir borte!

Study notes (Tyndale)

Original text and word study

Cross references