The Shadow is our dark side, which dictates how we should act and behave. When we try to free ourselves from the Persona, we turn on a light inside us and we see the cobwebs, the cowardice, the meanness. The Shadow is there to stop our progress, and it usually succeeds, and we run back to what we were before we doubted. However, some do survive this encounter with their own cobwebs, saying: "Yes, I have a few faults, but I'm good enough, and I want to go forward."
At this moment, the Shadow disappears and we come into contact with the Soul.
By Soul, Jung didn't mean "soul" in the religious sense; he speaks of a return to the Soul of the World, the source of all knowledge. Instincts become sharper, emotions more radical, the interpretations of signs becomes more important than logic, perceptions of reality grow less rigid. We start to struggle with things to which we are unaccustomed and we start to react in ways that we ourselves find unexpected.
And we discover that if we can channel that continuous flow of energy, we can organize it around a very solid center, what Jung calls the Wise Old Man and the Great Mother for women.
~ the novel, The Witch of Portobello, by Paulo Coelho