Before the reader encounters the actual text of John Bunyan’s religious narrative, they discover that The Pilgrim’s Progress is being told to them under “the Similitude of a Dream.” This lets the reader know that the story they’re about to read is a dream rather than an account of real life.
The dream is a crucial narrative device, because it allows Bunyan to present characters and situations that depart from reality without slipping into the realm of simple fantasy. By acknowledging from the start that the narrative is a dream, Bunyan tells the reader that what’s happening shouldn’t be mistaken for real life but should be interpreted as an allegory for the difficulties of trying to live a good Christian life.
For instance, when Christian is hampered by the Slough of Despond, he is, in a sense, stuck in a swamp. Yet because this narrative is a dream, one needs to think about what the Slough of Despond symbolizes, to consider how low spirits can bring on inertia or sluggishness.
Again, Bunyan’s dream-narrative device helps the reader follow Christian’s adventures like a story while, at the same time, compelling the reader to think about how Christian’s journey represents the hardships of remaining faithful to one’s religion. In many cases, the metaphorical or allegorical importance of each setting in the narrative is made explicit. As with the Slough of Despond, the symbolism of the stops on Christian’s narrative can be found in the names themselves. The Hill Difficulty is about difficulty, just as the Vanity Fair is about vanity.