'Business' in the Bible

And I set my mind to seek and explore by [man’s] wisdom all [human activity] that has been done under heaven. It is a miserable business and a burdensome task which God has given the sons of men with which to be busy and distressed.

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

There was a certain man—without a dependent, having neither a child nor a brother, yet there was no end to all his labor. Indeed, his eyes were not satisfied with riches and he never asked, “For whom do I labor and deprive myself of pleasure?” This too is vanity (a wisp of smoke, self-conceit); yes, it is a painful effort and an unhappy task.

For the dream comes through much effort, and the voice of the fool through many words.

When I applied my mind to know wisdom and to see the activities [of mankind] that take place upon the earth—how some men seem to sleep neither day nor night—