The appearance of them is as the appearance of horses; and as horsemen, so shall they run.
The appearance of them is as the appearance of horses. Not literal, but figurative locusts. The fifth trumpet, or first woe, in the parallel passage (Revelation 9:1-21) cannot be literal; for in Revelation 9:11 it is said, "They had a king over them, the angel of the bottomless pit-in the Hebrew Abaddon (Destroyer), but in the Greek Apollyon;" and (Revelation 9:7) "The shapes of the locusts were like unto horses prepared unto battle, and on their heads were as it were crowns like gold, and their faces were as the faces of men." Compare Joel 2:11, "The day of the Lord is great and very terrible;" implying their ultimate reference to be connected with Messiah's second coming in judgment. The locust's head is so like that of a horse that the Italians call it cavallette. Compare Job 39:20, "the horse ... as the grasshopper," or locust.
Run - the locust bounds, not unlike the horse's gallop, raising and letting down together the two front feet.