In Ezekiel 26:11, this signifies the love of learning or intellectual things. (Arcana Coelestia 3727)

In Revelation 6:2, this signifies the love of understanding the Word. (Apocalypse Revealed 298)

In Zechariah 12:4, this signifies that the intellectual should be filled with falsities. (Arcana Coelestia 2383[2])

In general, 'a horse' signifies knowledge or understanding of the Word. In an opposite sense it signifies the understanding of the Word falsified by reasonings, and likewise destroyed from self-derived intelligence. 'A dead horse' signifies no understanding of truth from the Word.

1377. The fact that place, change of place, or distance in the world of spirits is an appearance has been made clear from the consideration that all the souls and spirits that there have been since the beginning of creation appear to remain all the time in their own place. Nor does their place alter unless their state does. And as their state alters so are places and distances with them changed. But since everyone has a general governing state, and particular and individual changes of state nevertheless have regard to the general, spirits consequently go back after such changes to their own position.