'Beds of ivory' are the pleasures of the lowest part of the natural. 'Feeling no grief over the ruin of Joseph' stands for feeling no concern at all that good from the internal has been reduced to nothing. (Arcana Coelestia 6188)

In Amos 6:4, "beds of ivory" stand for doctrines seemingly from rational truths, and "to stretch themselves upon their couches" being to reason in favor of these from falsities.(Apocalypse Explained 1146[3])