For something to be cast down or cast out generally refers to a rather dramatic move from a higher spiritual state to a lower one. In most cases it's used in reference to evil desires or false thinking – or people spreading desires and false thinking – being removed and banished, even condemned to hell. Some uses are more moderate, though, and sometimes – when Moses casts down his rod in performing a miracle, for example – it signifies the sudden inflowing of the divine into the natural world.

(References: Apocalypse Explained 497, 1175; Apocalypse Revealed 252, 552, 835, 872; Arcana Coelestia 2657, 6693, 6948; The Apocalypse Explained 1181)