Ecclesiastes 4:4; Ecclesiastes 4:7-8

4 Then I saw all the labor and achievement that is the envy of a man's neighbor. This also is vanity and a striving after wind.

7 Then I returned and saw vanity under the sun.

8 There is one who is alone, and he has neither son nor brother. There is no end to all of his labor, neither are his eyes satisfied with wealth. For whom then, do I labor, and deprive my soul of enjoyment? This also is vanity, yes, it is a miserable business.