The defeat of Zerah is one of the most remarkable events in the history of the Jews. On no other occasion did they meet in the field and overcome the forces of either of the two great monarchies between which they were placed. It was seldom that they ventured to resist, unless behind walls. Shishak, Sennacherib, Esarhaddon, Nebuchadnezzar, were either unopposed or only opposed in this way. On the one other occasion on which they took the field - under Josiah against Necho - their boldness issued in a most disastrous defeat 2-Chronicles 35:20-24. Now, however, under Asa, they appear to have gained a complete victory over Egypt. The results which followed were nicest striking. The Southern power could not rally from the blow, and, for above three centuries made no further effort in this direction. Assyria, growing in strength, finally, under Sargon and Sennacherib, penetrated to Egypt itself. All fear of Egypt as an aggressive power ceased; and the Israelites learned instead to lean upon the Pharaohs for support (2-Kings 17:4; 2-Kings 18:21; Isaiah 30:2-4, etc.). Friendly ties alone connected the two countries: and it was not until 609 B.C. that an Egyptian force again entered Palestine with a hostile intention.

So the Lord smote the Ethiopians before Asa, and before Judah,.... With consternation and terror; they were thrown into a panic:
and the Ethiopians fled; before them, just as Jeroboam and Israel had, as related in the preceding chapter, 2-Chronicles 13:15.

Asa, with his people, pursued to Gerar, the old ancient Philistine city, whose ruins Rowlands has discovered in the Khirbet el Gerar, in the Wady Jorf el Gerar (the torrent of Gerar), three leagues south-south-east of Gaza (see on Genesis 20:1). "And there fell of the Cushites, so that to them was not revival," i.e., so many that they could not make a stand and again collect themselves, ut eis vivificatio i. e. copias restaurandi ratio non esset, as older commentators, in Annott. uberior. ad h. l., have already rightly interpreted it. The words are expressions for complete defeat. Berth. translates incorrectly: "until to them was nothing living;" for לאין does not stand for לאין עד, but ל serves to subordinate the clause, "so that no one," where in the older language אין alone would have been sufficient, as in 2-Chronicles 20:25; 1-Chronicles 22:4, cf. Ew. 315, c; and מחיה denotes, not "a living thing," but only "preservation of life, vivification, revival, maintenance." For they were broken before Jahve and before His host. מחנהוּ, i.e., Asa's army is called Jahve's, because Jahve fought in and with it against the enemy. There is no reason to suppose, with some older commentators, that there is any reference to an angelic host or heavenly camp (Genesis 32:2.). And they (Asa and his people) brought back very much booty.

Smote - With terror, and an unaccountable consternation.