Strength of the horse... legs of a man. — This somewhat strange antithesis has been explained to refer to cavalry and infantry, but the much more expressive passage, Psalms 33:16-17, which was plainly before this poet, would hardly have been altered so strangely. The horse as a type of strength and endurance was of course common. (Comp. especially Job 39:19-25.) And we have before seen that Eastern nations naturally select fleetness of foot as the typical quality in a vigorous warrior. (See Psalms 18:33.)
The constant epithet “swift-footed Achilles,” suggests the best explanation of the second clause of the verse. (Comp. 2 Samuel 2:18).