Ecclesiastes 1:13

“Man puts an end to darkness, And to the farthest limit he searches out The rock in thick darkness and shadow of death.

And I gave my heart to know wisdom and to know madness and simpleminded folly; I came to know that this also is striving after wind.

I have seen the endeavor which God has given the sons of men with which to occupy themselves.

There was a certain man without a second man, having neither a son nor a brother, yet there was no end to all his labor. Indeed, his eyes were not satisfied with riches—“And for whom am I laboring and depriving myself of good?” This too is vanity, and it is a grievous endeavor.

When I gave my heart to know wisdom and to see the endeavor which has been done on the earth (even though one never sees sleep with his eyes day or night),

Just as you do not know the path of the wind and how bones are formed in the womb of the pregnant woman, so you do not know the work of God who works all things.