'Works' in the Bible

I have seen all the works that are done under the sun; and, behold, all is vanity and a striving after wind.

I made me great works; I builded me houses; I planted me vineyards;

Then I looked on all the works that my hands had wrought, and on the labor that I had labored to do; and, behold, all was vanity and a striving after wind, and there was no profit under the sun.

Wherefore I saw that there is nothing better, than that a man should rejoice in his works; for that is his portion: for who shall bring him back to see what shall be after him?

For all this I laid to my heart, even to explore all this: that the righteous, and the wise, and their works, are in the hand of God; whether it be love or hatred, man knoweth it not; all is before them.

Go thy way, eat thy bread with joy, and drink thy wine with a merry heart; for God hath already accepted thy works.