Listen to Bible (KJV) 21: Ecclesiastes on your phone!
The book of Ecclesiastes is a wonderful book. It tells how all man's doing is futile, if it is done in his own strength. The last two verses sum it up quite nicely: "Let us hear the conclusion of the whole matter: Fear God, and keep his commandments: for this is the whole duty of man. For God shall bring every work into judgment, with every secret thing, whether it be good, or whether it be evil. (Summary by GabrielleC)