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

(References: Arcana Coelestia 2418)

8510. 'That some of the people went out to gather, and did not find' means that they wished to acquire it, but none was given. This is clear from the explanation above in 8505. The explanation there shows what actions springing from the truth of faith are and what those springing from the good of charity are. That is to say, it shows that a person whose actions spring from the truth of faith does not as yet have the order of heaven present in himself, whereas one whose actions spring from the good of charity does have it. For, according to order, when the Lord leads a person He does so through his will, consequently through good since this belongs properly to the will. In that case his understanding is subservient, and so is truth since this belongs properly to the understanding. When this state exists it is the sabbath, for then there is rest for the Lord; and the state comes into being once good has been joined to truth. That this state is the Lord's rest may be recognized from the statement that after six days of creation and labour Jehovah or the Lord rested on the seventh day from all His work, Genesis 2:2. This state is heaven's state, which explains why heaven itself is called the sabbath, and that in heaven the sabbath is perpetual. For the creation story in Genesis 1 serves to mean the new creation, which is regeneration, and the six days in the story serves to mean temptations and conflicts, see the explanations at Genesis 1, 2.