Here is, I. Disturbance given to the peace of Asa's kingdom by a formidable army of Ethiopians that invaded them, Ch2 14:9, Ch2 14:10. Though still they sought God, yet this fear came upon them, that their faith in God might be tried, and that God might have an opportunity of doing great things for them. It was a vast number that the Ethiopians brought against him: 1,000,000 men; and now he found the benefit of having an army ready raised against such a time of need. That provision which we thought needless may soon appear to be of great advantage.
II. The application Asa made to God on occasion of the threatening cloud which now hung over his head, Ch2 14:11. He that sought God in the day of his peace and prosperity could with holy boldness cry to God in the day of his trouble, and call him his God. His prayer is short, but has much in it. 1. He gives to God the glory of his infinite power and sovereignty: It is nothing with thee to help and save by many or few, by those that are mighty or by those that have no power. See Sa1 14:6. God works in his own strength, not in the strength of instruments (Psa 21:13), nay, it is his glory to help the weakest and to perfect strength out of the mouth of babes and sucklings. "We do not say, Lord, take our part, for we have a good army for thee to work by; but, take our part, for without thee we have no power." 2. He takes hold of their covenant-relation to God as theirs. O Lord, our God! and again, "Thou art our God, whom we have chosen and cleave to as ours, and who hast promised to be ours." 3. He pleads their dependence upon God, and the eye they had to him in this expedition. he was well prepared for it, yet trusted not to his preparations; but, "Lord, we rest on thee, and in thy name we go against this multitude, by warrant from thee, aiming at thy glory, and trusting to thy strength." 4. He interests God in their cause: "Let not man" (mortal man, so the word is) "prevail against thee. If he prevail against us, it will be said that he prevails against thee, because thou art our God, and we rest on thee and go forth in thy name, which thou hast encouraged us to do. The enemy is a mortal man; make it to appear what an unequal match he is for an immortal God. Lord, maintain thy own honour; hallowed by thy name."
III. The glorious victory God gave him over his enemies. 1. God defeated the enemy, and put their forces into disorder (Ch2 14:12): The Lord smote the Ethiopians, smote them with terror, and an unaccountable consternation, so that they fled, and knew neither why nor whither. 2. Asa and his soldiers took the advantage God gave them against the enemy. (1.) They destroyed them. They fell before the Lord (for who can stand before him?) and before his host, either an invisible host of angels that were employed to destroy them or the host of Israel, called God's host because owned by him. (2.) They took the plunder of their camp, carried away very much spoil from the slain and from the baggage. (3.) They smote the cities that were in league with them, to which they fled for shelter, and carried off the spoil of them (Ch2 14:14); and they were not able to make any resistance, for the fear of the Lord came upon them, that is, a fear which God struck them with to such a degree that they had no heart to withstand the conquerors. (4.) They fetched away the cattle out of the enemy's country, in vast numbers, Ch2 14:15. Thus the wealth of the sinner is laid up for the just.

Zerah the Ethiopian - Probably of that Ethiopia which lay on the south of Egypt, near to Libya, and therefore the Libyans are joined with them, Ch2 16:8.
A thousand thousand - If this people had come from any great distance, they could not have had forage for such an immense army.

And Asa cried unto the Lord his God,.... Or prayed, as the Targum, with vehemence, being in distress; this he did before the battle began, at the head of his army, and for the encouragement of it:

and said, Lord, it is nothing with thee to help; nothing can hinder from helping, his power being superior to all others, and even infinite, and none besides him could:

whether with many, or with them that have no power; numbers make no difference with him, nor the condition they are in; whether numerous and mighty, or few and feeble; he can as easily help the one as the other, see Sa1 14:6,

help us, O Lord our God; who are few and weak in comparison of the enemy:

for we rest on thee; trust in thee, and rely upon thee for help; the Targum is,"on thy Word we lean:"

and in thy name we go against this multitude; expressing faith in him, expecting help from him, encouraging and strengthening themselves in him, going forth not in their own name and strength, but in his; the Targum is,"in the name of the Word of the Lord:"

O Lord, thou art our God: and thou only we know, and serve no other, and we are thy people, called by thy name:

let not man prevail against thee; for should this enemy prevail against them, it would be interpreted prevailing against their God.

Then Asa went out against him, and they set the battle in array . . . at Mareshah--one of the towns which Rehoboam fortified (Ch2 11:8), near a great southern pass in the low country of Judah (Jos 15:44). The engagement between the armies took place in a plain near the town, called "the valley of Zephathah," supposed to be the broad way coming down Beit Jibrin towards Tell Es-Safren [ROBINSON].