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 most cases, the meaning of "before" is pretty straightforward, both as a way of assessing relative time, and in its use meaning "in someone's presence." It takes on a deeper significance, though, when used in connection with the Lord. To be "before" the Lord means not just in His presence, but also receiving the desire for good and the understanding of truth from Him, and living according to them. And when used as an assessment of time in connection with the Lord, "before" means "from eternity," and refers to a spiritual state rather than time as we experience it.

(References: Apocalypse Revealed 366, 617; Arcana Coelestia 6983, 8439, 9888)