The expression 守株待兔 (shou3 zhu1 dai4 tu4) literally means standing by a tree stump waiting for a hare to crash into it.
Long ago in the State of Song, there was a farmer labouring in the fields. One day he saw a hare race past him and crash headlong into a tree stump a few metres away. The hare was knocked unconscious (or we could say, it had brained itself). The farmer picked up the hare and took it home to prepare a tasty dinner. After have a few (alcoholic) drinks, he began to think that the stump in his field might be blessed and that if he could get just one hare a day, he would never have to work the fields again.
So, beginning the next day, the farmer stopped tending his crops and waited by the stump for more hares to come along and brain themselves. Needless to say, this harebrained scheme did not work. He waited several days and no hares came. Meanwhile his field became overgrown and he became the laughing stock of the local area.
The English idiomatic expressions that express a similar sentiment are waiting for something to fall into one's lap and there is no such thing as a free lunch. Both the English and Chinese idioms provide a warning against being lazy, stupid and trusting one's fate to chance. Few people achieve anything (or at least anything of note) in their life without some hard work and perseverance. Despite the obvious truth in this advice, the Song farmer still has a strong army of followers even today. In a world wher parents increasingly spoil their children, it behoves us all to remember that raising children without instilling some sort of work ethic does them a huge disservice.