Can you give us more information? What story are you reading?
Answer:
1) The rhetorical strategy is to use a simile to provide a clear image of justice.
2) The purpose of this strategy is to emphasize and express how they feel.
3) The person saying this quote did this to give the audience a clear sense of justice and how dedicated the person is to whatever justice they are trying to serve.
4) "until Justice rolls down like waters and righteousness like a mighty stream." As in "mighty stream" the person means a "large group of people" that contributes to making the justice happen.
The films are usually more comical and easier to understand. I think, I've only read the book twice.
