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 Jeremiah 33:26, this signifies people who are in spiritual divine truth, and people who are in natural-spiritual divine truth. (Apocalypse Explained 768[17], Divine Love and Wisdom 43, 44)