1 Samuel 14:15

And there was trembling in the host. — The rest of the outpost garrison, panic-stricken, escaped to the other camp of the main body of the host, spreading dismay as they fled.

And the earth quaked... — To add to the dire confusion, an earthquake was felt, which completed the discomfiture of the Philistines; they perceived that some Divine power was fighting against them, and all the stories of the unseen Helper of the Hebrews would flash across their minds. Some would explain the earthquake as a poetical description of the extreme terror and confusion which prevailed far and near, but the literal meaning is far the best. The Eternal fought for Jonathan and Israel that day, and the powers of nature were summoned to the young hero’s aid, as they had been before, when Pharaoh pursued the people at the Red Sea (Exodus 14:26), as when Joshua fought the Canaanites at Beth-horon (Joshua 10:11), and as when Barak smote Sisera at Kishon (Judges 5:21).