In the Bible, things that are lower down, or under, physically, generally represent things that are lower or more external spiritually. In some cases, the lower things have been separated and put away to protect the good, but in others, it can mean that a less exalted idea or good desire is supporting a more exalted one.

(References: Arcana Coelestia 4564 [1-2], 8610, 9656)

In Genesis 8:22, this signifies the alternating states in intellectual matters of a regenerate person. (Arcana Coelestia 936)

In Isaiah 13:6 and Jeremiah 6:4, this stands for the state associated with that particular time. (Arcana Coelestia 23, 487)