By reason of the abundance of his horses their dust shall cover thee: thy walls shall shake at the noise of the horsemen, and of the wheels, and of the chariots, when he shall enter into thy gates, as men enter into a city wherein is made a breach.

His multitude of horses will cover you in their dust. When he enters your gates as an army entering a breached city, your walls will shake from the noise of cavalry, wagons, and chariots.