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)

'Washing of the hands' was an ancient declaration of innocence, and signifies purification from evils and falsities, as in Psalms 73:13 and Matthew 27:24.

(References: Apocalypse Explained 475)