Who made them walk through the depths. These things are added for the purpose of setting that benefit in a stronger light. He likewise brings forward comparisons, in order to describe that extraordinary power of God: "As a horse in the desert, As a beast into a plain;" that is, he led out his people as gently as if one were leading a horse into a plain. By the word "desert" is not meant the wilderness of Paran in which the people dwelt forty years; but, in accordance with the ordinary usage of the Hebrew tongue, it denotes pasture, in which herds and flocks wander at large. This is still more evident from the following verse, --

That led them through the deep - They went through the deep on dry land - the waters having divided and left an unobstructed path.
As an horse in the wilderness - As an horse, or a courser, goes through a desert without stumbling. This is a most beautiful image. The reference is to vast level plains like those in Arabia, where there are no stones, no trees, no gullies, no obstacles, and where a fleet courser bounds over the plain without any danger of stumbling. So the Israelites were led on their way without falling. All obstacles were removed, and they were led along as if over a vast smooth plain. Our word 'wilderness,' by no means expresses the idea here. We apply it to uncultivated regions that are covered with trees, and where there would be numerous obstacles to such a race-horse. But the Hebrew word (מדבר midbâr) rather refers to "a desert, a waste" - a place of level sands or plains where there was nothing to obstruct the fleet courser that should prance over them. Such is probably the meaning of this passage, but Harmer (Obs. i. 161ff) may be consulted for another view, which may possibly be the correct one.

That led them through the deep - As a beast goeth down into the valley - In both these verses there is an allusion to the Israelites going through the Red Sea, in the bottom of which they found no more inconvenience than a horse would in running in the desert, where there was neither stone nor mud; nor a beast in the valley, where all was plain and smooth.

That led them through the deep, as an (o) horse in the wilderness, [that] they should not stumble?
(o) Peaceably and gentle, as a horse is led to his pasture.

That led them through the deep,.... The depths, the bottom of the sea; not through the shallow, but where the waters had been deepest, the descent greatest; and at the bottom of which might have been expected much filth and dirt to hinder them in their passage, yet through this he led them:
as an horse in the wilderness; or rather, "in a plain", as the word (b) sometimes signifies; and so Kimchi renders it a plain land, and Jarchi smooth land. The sense is, that the Israelites passed through the sea with as much ease, and as little difficulty, as a good horse will run over a plain, where there is nothing to stop his course:
that they should not stumble? there being no clay to stick in, no stone to stumble at, but all like an even plain.
(b) "in planitie", Calvin, Gataker, Vitringa; "in campis", Grotius.

deep--literally, "the tossing and roaring sea."
wilderness--rather, the "open plain" [HORSLEY], wherein there is no obstacle to cause a horse in its course the danger of stumbling.

As an horse - With as much ease and tenderness, as an horse led by the bridle. Not stumble - That, tho' the sea were but newly divided, yet it was dried and smoothed by the wind, that God sent, as it were to prepare the way before them.