1 Samuel 7:3-10

So Samuel said to all the Israelites, “If you are returning to the LORD with all your hearts, then rid yourselves of the foreign gods and the Ashtoreths and commit yourselves to the LORD and serve him only, and he will deliver you out of the hand of the Philistines.” So the Israelites put away their Baals and Ashtoreths, and served the LORD only. Then Samuel said, “Assemble all Israel at Mizpah, and I will intercede with the LORD for you.” When they had assembled at Mizpah, they drew water and poured it out before the LORD. On that day they fasted and there they confessed, “We have sinned against the LORD.” Now Samuel was serving as leader of Israel at Mizpah. When the Philistines heard that Israel had assembled at Mizpah, the rulers of the Philistines came up to attack them. When the Israelites heard of it, they were afraid because of the Philistines. They said to Samuel, “Do not stop crying out to the LORD our God for us, that he may rescue us from the hand of the Philistines.” Then Samuel took a suckling lamb and sacrificed it as a whole burnt offering to the LORD. He cried out to the LORD on Israel’s behalf, and the LORD answered him. While Samuel was sacrificing the burnt offering, the Philistines drew near to engage Israel in battle. But that day the LORD thundered with loud thunder against the Philistines and threw them into such a panic that they were routed before the Israelites.