I Samuel 14:20-23

Then Saul and all the people who were with him assembled, and they went to the battle; and indeed every man’s sword was against his neighbor, and there was very great confusion. Moreover the Hebrews who were with the Philistines before that time, who went up with them into the camp from the surrounding country, they also joined the Israelites who were with Saul and Jonathan. Likewise all the men of Israel who had hidden in the mountains of Ephraim, when they heard that the Philistines fled, they also followed hard after them in the battle. So the LORD saved Israel that day, and the battle shifted to Beth Aven.