1 Samuel 7:10
And as Samuel was offering up the burnt offering, the Philistines drew near to battle against Israel: but the LORD thundered with a great thunder on that day upon the Philistines, and discomfited them; and they were smitten before Israel.
The verse belongs to the history when Samuel stayed true to Heaven amid surrounding evil, while the sins of Eli and his sons shut out the presence of God's Holy Spirit, and the message of condemnation to the house of Eli was his commission as a prophet of the Most High. It comes after Israel had been under the power of the Philistines for twenty years while the ark was in the house of Abinadab, during which they were greatly humbled and repented of their sins, Samuel interceded for them, and God was again merciful to them. It shows Samuel in his youth, when he began to judge Israel, calling the people together for fasting and prayer and deep humiliation before God and bearing solemn testimony from the mouth of God.
At that time Israel learned where their strength lay and entreated Samuel to cry unceasingly to God for them when their enemies were aroused to meet them in battle. While Samuel was in the act of presenting a lamb as a burnt offering, the Philistines drew near for battle against Israel. God then manifested His power as He had at Sinai amid fire and smoke and thunder, at the Red Sea, and at the Jordan, thundering with great thunder upon the Philistines and sending a terrible storm upon the advancing host that discomfited them and left the earth strewn with the dead bodies of mighty warriors.
God heard prayer in their behalf and acted again in a miraculous manner for Israel, turning the Philistine attack into a decisive victory so that Israel overcame their enemies, with victory turning to the side of Israel as they pursued the fleeing enemy though unprepared for battle. The slaughter of the Philistines showed the Israelites that God had accepted their repentance, and this victory came on the same field where Israel had been defeated twenty years earlier and the ark had been taken. The event teaches that obedience to God brings safety and happiness while transgression leads to disaster and defeat, and after the victory the Philistines surrendered Israel's strongholds and long refrained from hostilities.