James 4:14

Whereas ye know not what shall be on the morrow
Whether there would be a morrow for them or not, whether they should live till tomorrow; and if they should, they knew not what a morrow would bring forth, or what things would happen, which might prevent their intended journey and success: no man can secure a day, an hour, a moment, and much less a year of continuance in this life; nor can he foresee what will befall him today or tomorrow; therefore it is great stupidity to determine on this, and the other, without the leave of God, in whom he lives, moves, and has his being; and by whose providence all events are governed and directed; see ( Proverbs 27:1 )

for what is your life?
of what kind and nature is it? what assurance can be had of the continuance of it? by what may it be expressed? or to what may it be compared?

it is even a vapour that appeareth for a little time, and then
vanisheth away;
which rises out of the earth, or water, and expires almost as soon as it exists; at least, continues but a very short time, and is very weak and fleeting, and carried about here and there, and soon returns from whence it came: the allusion is to the breath of man, which is in his nostrils, and who is not to be accounted of, or depended on.