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

(References: Arcana Coelestia 2418)

3485. The representations that occur in the next life are appearances. But they are living representations because they come from the light of life. The light of life is Divine Wisdom, which is received from the Lord alone. Consequently all things that come into being from that light, unlike those from the light of the world, are real. For this reason people in the next life have said several times that the things they behold in that world are real, whereas those that man beholds are by contrast not real. The reason for this is that the former are living and so have a direct influence on their life, whereas the latter are not living and so have no direct influence on their life, except insofar as things with them belonging to the light of the world join themselves appropriately and by correspondence to those belonging to the light of heaven. From all these considerations it now becomes clear what representations are and what correspondences are.