Arcana Coelestia # 7024
7024. And he made them ride upon the ass. That this signifies the things that would be of service to new intelligence, is evident from the signification of “riding,” as being the things of the intellect, here of new intelligence, which must be of life among those who are in the spiritual church (see n. 7016); that these things are signified by “riding” is because a “horse” signifies the intellectual (of which see n. 2761, 2762, 3217, 5321, 6534); and from the signification of an “ass,” as being the truth that is of service, here to new intelligence (n. 2781, 5741), and also as being memory-knowledge (n. 5492).
Arcana Coelestia # 3217
3217. When the angels are discoursing of that which relates to the understanding, then in the world of spirits, beneath the angels, or in the corresponding societies, there appear horses; and these of a size, form, color, attitude, and varied equipment, in accordance with the ideas which the angels have concerning the understanding. There is also a place at some depth a little to the right, which is called the abode of the intelligent, where horses continually appear, and this by reason of those present being in thought about what is of the understanding; and when angels whose discourse is about this subject flow into their thoughts, there is a representation of horses. This shows what was signified by the horses seen by the prophets, and also by the horses mentioned elsewhere in the Word; namely, the things of the understanding (n. 2760-2762).