Now Asa knew how to pray! Those who would say God doesn't take sides would be wrong. Note King Asa didn't defeat the Ethiopians, they fled before the Lord.

2 Chronicles 14:9-13
Zerah the Ethiopian came out against them with an army of a million men and 300 chariots, and came as far as Mareshah.
And Asa went out to meet him, and they drew up their lines of battle in the Valley of Zephathah at Mareshah.

And Asa cried to the Lord his God, “O Lord, there is none like you to help, between the mighty and the weak. Help us, O Lord our God, for we rely on you, and in your name we have come against this multitude. O Lord, you are our God; let not man prevail against you.”
So the Lord defeated the Ethiopians before Asa and before Judah, and the Ethiopians fled.
Asa and the people who were with him pursued them as far as Gerar, and the Ethiopians fell until none remained alive, for they were broken before the Lord and his army. The men of Judah carried away very much spoil.
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