In the previous verses, the psalmist complains that life is miserable, and wants to know how much longer life will be, for enduring that misery. And in this verse, the psalmist complains that life is too short, that it is meaningless, that it is so brief, making accomplishment virtually impossible.
Complaining, typically contradicts itself. The complainer wants one thing, and then he wants another.
And in this verse, the word for handbreadth, is a reference to the width of the hand, or meaning something that is very small in measurement.
The psalmist complains that his age, meaning his life, is the same as nothing.
And the general reference to man, meaning mankind on the whole, or the entire history of mankind, is likewise, nothing.
The implication is, why doesn’t God give longer lives, so that something can be accomplished.
But on the other hand, life is full of miserable things, one after another. And if a person had a longer life, then they would just have to suffer or endure, many more miserable things.
And besides the very first generations had lifespans of hundreds of years, and all it got them was a flood.
This is the Devils world, and as such, on a good day, the world can offer nothing more than miserable things.
And at some point in everyone’s life, the inconsistencies of complaining, will bubble to the surface, and one can only think that God will smile, upon hearing the flip-flop argument that a person generates by them self, while talking to them self, while complaining to God.
If life is miserable, and offers no meaning or purpose, then isn’t it possible that a person would look to God, and doctrine, and the spiritual life, to discover their real meaning and purpose?
After all, one who is complaining to God, and in effect is speaking to God, then by default recognizes that there is something beyond this life, and therefore something better. So why not pursue it?