Justice and Mercy
Harry Potter and the Prisoner of AzkabanThe moral dilemma of whether to kill Pettigrew or show mercy, and the consequences of Harry's choice.
increasing
Bearing strength in each event
decreasing
The desire for revenge

The Fury
Sirius and Lupin's Need
Sirius and Lupin want to kill Pettigrew for his betrayal. They have waited twelve years for justice. They are ready to kill him without hesitation.
Harry's Conflict
Harry initially wants revenge too. He has hated Black for months. But when he sees Pettigrew groveling, he hesitates. He thinks of what his father would want.
The Decision
Harry decides that killing Pettigrew is not the answer. He argues that his father wouldn't want them to become murderers. He insists on handing Pettigrew over to the Dementors.
The mercy saves a life

The Unforeseen Consequence
The Escape
Despite the mercy, Pettigrew escapes due to Lupin's transformation. He is now free to rejoin Voldemort. Harry worries that his mercy will lead to disaster.
Dumbledore's Wisdom
Dumbledore explains that Pettigrew now owes Harry a life debt. This may one day prove advantageous. He tells Harry that saving Pettigrew was a noble act.
The Theme
The theme of mercy over revenge is explored. Harry's choice to spare Pettigrew, even though it leads to danger, is shown to be morally right. The story suggests that justice tempered with mercy is the path of a true hero.
Shrieking Shack
Later, after Pettigrew escapes