We are created in such a way that we are in the spiritual world and the earthly world at one and the same time. The spiritual world is where angels are and the earthly world is where we are. And since that is how we are created, we are given an inner nature and an outer nature—an inner nature that allows us to be in the spiritual world, and an outer nature that allows us to be in the earthly world. Our inner nature is what we refer to as the inner self, and our outer nature is what we refer to as the outer self.
Each one of us has an inner level and an outer level, but they are not the same for good people as they are for evil ones. For good people, their inner level is in heaven and in its light, while their outer level is in the world and in its light. Further, for good people this latter light is brightened by heaven’s light, so their inner and outer levels act in unison like an efficient cause and its effect, or like what is prior and what is subsequent. For evil people, though, their inner level is in this world and its light, and the same holds true for their outer level as well. This means that they cannot see anything in heaven’s light, only in this world’s light, which they call “the light of nature.” That is why heavenly matters are in darkness for them and worldly matters are in the light.
We can see from this that good people have an inner self and an outer self, while [in effect] evil people have no inner self, only an outer one.
from New Jerusalem, Sections 36, 37