Cities of the mountain and cities of the plain (Jeremiah 33:13) signify doctrines of charity and faith.

(References: Arcana Coelestia 2418)

4415. Recently arrived souls, or novitiate spirits - that is to say, people who a few days after death of the body have entered the next life - are utterly amazed at the existence of light in the next life, for they bring with them the uninformed idea that there are no other sources of light than the sun and material flame. Still less do they know of a light which brings light to the understanding, for they have not observed it during their lifetime; and still less that such light provides the capacity to think, and by flowing into forms which exist from the light of the world frames everything seen in the understanding. If those novitiate spirits have been good people they are raised up, for the purpose of their instruction, to heavenly communities, passing from one community to another. They are raised up to these so that they may recognize through actual experience that light exists in the next life, a light that is brighter than that which shines in the world can ever be, and that the amount of light they dwell in there determines the amount of intelligence. Some borne up into spheres of heavenly light have spoken to me from there, confessing that they had never believed in any such thing and that the light of the world in comparison was darkness. From there they also looked through my eyes into the light of the world, which they saw to be nothing other than dark cloud. And they said, doing so with feelings of pity, that such was the darkness in which men dwelt. From what has been said one may also see why in the Word the angels of heaven are called angels of light; also that the Lord is the Light, and consequently the Life, for men, John 1:1-8; 8:12.