1st Samuel 7:8

5 Then Samuel said, Let all Israel come to Mizpah and I will make prayer to the Lord for you.

6 So they came together to Mizpah, and got water, draining it out before the Lord, and they took no food that day, and they said, We have done evil against the Lord. And Samuel was judge of the children of Israel in Mizpah.

7 Now when the Philistines had news that the children of Israel had come together at Mizpah, the lords of the Philistines went up against Israel. And the children of Israel, hearing of it, were full of fear.

8 And the children of Israel said to Samuel, Go on crying to the Lord our God for us to make us safe from the hands of the Philistines.

9 And Samuel took a young lamb, offering all of it as a burned offering to the Lord; and Samuel made prayers to the Lord for Israel and the Lord gave him an answer.

10 And while Samuel was offering the burned offering, the Philistines came near for the attack on Israel; but at the thunder of the Lord's voice that day the Philistines were overcome with fear, and they gave way before Israel.

11 And the men of Israel went out from Mizpah and went after the Philistines, attacking them till they came under Beth-car.