Horse
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.
Exodus 33:1-3
1
Yahweh spoke to Moses, "Depart, go up from here, you and the people that you have brought up out of the land of Egypt, to the land of which I swore to Abraham, to Isaac, and to Jacob, saying, 'I will give it to your seed.'
2
I will send an angel before you; and I will drive out the Canaanite, the Amorite, and the Hittite, and the Perizzite, the Hivite, and the Jebusite:
3
to a land flowing with milk and honey: for I will not go up in the midst of you, for you are a stiff-necked people, lest I consume you in the way."