Generally speaking things that are seen as lower physically in the Bible represent things that are lower or more external spiritually. In some cases this means things that have been separated and put away for the protection of what is good, but it can also be a less exalted idea or good desire that supports a more exalted one.
Passages from Swedenborg
Arcana Coelestia (Elliott) n. 4564
4564. ‘And was buried below Bethel under an oak’ means cast away for ever. This is clear from the meaning of ‘being buried’ as being cast away, for that which is buried is cast away; and from the meaning of ‘under an oak’ as for ever, dealt with above in 4552. ‘Below Bethel’ means outside the natural, for that which is said to be beneath or below is in the internal sense outside, 2148; ‘Bethel’ is the Divine Natural 4089, 4539.
[2] The implication of this is that with a person who is being regenerated,
neither hereditary evil nor that of his own doing is removed in such a way as to disappear or be eliminated, but is merely separated and through the
rearrangement effected by the Lord is cast away to the most outlying parts, 4551, 4552. It accordingly remains with that person, and does so for ever, but he is withheld from evil by the Lord and maintained in good. When this happens it seems as though evils have been cast away and the person has been purified from them or, as it is said, made righteous. All the angels of heaven confess that in their case, insofar as anything originates in themselves it is entirely evil and consequently false, but insofar as it originates in the Lord it is good and consequently true.
Arcana Coelestia (Elliott) n. 8610
8610. ‘And put it under him, and he sat on it’ means correspondence with the highest level of truth. This becomes clear from the consideration that the stone supported Moses and ‘Moses’ represents the highest level of truth, which is God’s truth that goes forth directly from the Lord. When the lowest level of truth corresponds with this highest level of truth it supports it, for they act as one. Interior truths are joined to exterior, and finally to the lowest through the correspondence [of each level with the one above it]. Highest truth then has might within the lowest, because it resides in it and acts through it. But if there is no such correspondence they are disjoined, and consequently highest truth has no might within lowest.
Arcana Coelestia (Elliott) n. 9656
9656. ‘And they shall be paired from below, and at the same time paired up to its head’ means a joining together from without and from within. This is clear from the meaning of ‘being paired’ as being made to act jointly; from the meaning of ‘from below’ as from without, since the Word portrays what exists outwardly as that which is below, and what exists inwardly as that which is above, 3084, 4599, 5146, 8325 (so that things deep down are more outward and those high up more inward, 2148, 4210, 4599); and from the meaning of ‘the head’, in the expression ‘from below up to the head’, as from within. The reason why ‘the head’ has this meaning is that the head is above the body, and by things above are meant those that are inward, as has just been stated; and in addition to this a person’s inward powers are located in the head, for in it reside the beginnings of the senses and motions, and the beginnings are inmost because they are the source from which everything else flows. These beginnings are like wellsprings from which streams of water flow