Pilgrim's Progress Lesson Plan

How do the scenes in the Interpreter's house relate to Bunyan's defense (in his introduction to both books) of using metaphors to convey his ideas?

The scenes at the Interpreter's house, in both Christian and Christiana's sections, show readers how metaphors can be useful and instructive. For example, the Interpreter shows Christiana a man raking muck with his eyes trained on the floor, all while a heavenly being is standing above him and offing him a celestial crown. This is a metaphor for the problem with fixating on worldly, carnal desires. Bunyan shows how these metaphors make truths of the Christian faith clear and understandable to his characters, implying that...