§ 02 · King James Bible
James 4:14
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.
Simple English
Since you don't know what tomorrow will bring. Your life is like a short-lived mist that appears for a moment and then disappears.
* Work in progress - there may be occasional inaccuracies