Shakespeare's play, Hamlet, is about a man trying to avenge his father's death. 
            
 Hamlet is a person that fails to act on killing the king on several occasions.  Hamlet
            
 eventually gets his revenge on the king who murdered his father, but he had many chances
            
 to kill the king before he got his revenge.  
            
  One example of Hamlet passing a chance to kill the king is when the king was
            
 on his knees praying.  Hamlet had his dagger out, ready to kill the king but he did not do it
            
 because, in the time period that Hamlet took place, they believed that if you killed someone
            
 while they were praying, then that person would go to heaven no matter what crime they
            
 committed.  In the play, Hamlet says, "Now might I do  't pat, now  'a is a-praying; And now
            
 I'll do  't.  And so  'a goes to heaven, and so am I revenged.  That would be scanned." 
            
 After that Hamlet goes on to say "When he is drunk asleep, or in his rage, or in th'
            
 incestuous pleasure of his bed, at game, a-swearing, or about some act that has no relish
            
 of salvation in  't then trip him, that his heels may kick at heaven, as hell, whereto it goes." 
            
 So knowing that the king would not go to hell if he killed him while he was praying, he did
            
  Hamlet had another chance to kill the king when the king was at the play Hamlet
            
 was putting on.  Hamlet and the king were sitting right next to each other talking about
            
 the play.  Hamlet could have killed him at the play, but he did not do it because he needed
            
 more evedence that the king killed his father.  That is why Hamlet wanted to show the
            
 play because in the play the pretend king gets killed the same way Hamlet's father did, so
            
 Hamlet thought that if the king started acting funny after that then he would have all the
            
 evedence he needed.  When the pretend king got poisoned in the play, the king jumped up
            
 and said "Give me some light. Away!"  The king then left the play and Hamlet new that
            
 what the ghost was ...