Allegory

An extended form of a metaphor, in which objects, people, and actions in a narrative are equated with meanings that lie outside of the narrative. The underlying meaning has moral, social, religious, or political significance. Characters are often personifications of abstract ideas, such as, greed, envy, hatred, or happiness. Allegories have a literal meaning and a symbolic meaning.

Example: Dante's journey through Hell, Purgatory, and Paradise in La Divina Comedia (The Divine Comedy) is an allegory of humanity's recognition and purification of sin, and finally accepting the light of God. Dante himself becomes a metaphor for humanity- his guide, Virgil, a metaphor for human reason.