John Trapp on Joel 2:4

Verſe 4. The appearance of them is as the appearance of horſes: and as horſemen,] i. e. the Locuſts, and other Inſects come on amain: they march with much nimbleneſſe and ſwiftneſſe. An horſe is a warlike creature, full of terrour: [non-Latin text not transcribed]. Pauſan. ſo ſwift in ſervice, that the Perſians dedicated him to their god, the Sun, as the ſwifteſt creature to the ſwifteſt god. See Job 41.20. Prov. 21.31. In Perſia they do all, almoſt on horſeback: they buy, ſell, confer, but eſpecially fight on horſeback to this day. So they did of old; and ſo did the Chaldeans, from whom they took the Monarchy. Theſe were horſemen, and not as horſemen: this place therefore is properly and principally to be underſtood of the locuſts. Confer Rev. 9.7.