When the Philistines heard that David had been designated king over Israel, they all went up to search for David. When David heard about it, he went down to the fortress. Now the Philistines had arrived and spread out in the valley of Rephaim. So David asked the Lord, "Should I march up against the Philistines? Will you hand them over to me?" The Lord said to David, "March up, for I will indeed hand the Philistines over to you." read more.
So David marched against Baal Perazim and defeated them there. Then he said, "The Lord has burst out against my enemies like water bursts out." So he called the name of that place Baal Perazim. The Philistines abandoned their idols there, and David and his men picked them up. The Philistines again came up and spread out in the valley of Rephaim. So David asked the Lord what he should do. This time the Lord said to him, "Don't march straight up. Instead, circle around behind them and come against them opposite the trees. When you hear the sound of marching in the tops of the trees, act decisively. For at that moment the Lord is going before you to strike down the army of the Philistines." David did just as the Lord commanded him, and he struck down the Philistines from Gibeon all the way to Gezer.

2 Samuel 23:9-16

Next in command was Eleazar son of Dodo, the son of Ahohi. He was one of the three warriors who were with David when they defied the Philistines who were assembled there for battle. When the men of Israel retreated, he stood his ground and fought the Philistines until his hand grew so tired that it seemed stuck to his sword. The Lord gave a great victory on that day. When the army returned to him, the only thing left to do was to plunder the corpses. Next in command was Shammah son of Agee the Hararite. When the Philistines assembled at Lehi, where there happened to be an area of a field that was full of lentils, the army retreated before the Philistines. read more.
But he made a stand in the middle of that area. He defended it and defeated the Philistines; the Lord gave them a great victory. At the time of the harvest three of the thirty leaders went down to David at the cave of Adullam. A band of Philistines was camped in the valley of Rephaim. David was in the stronghold at the time, while a Philistine garrison was in Bethlehem. David was thirsty and said, "How I wish someone would give me some water to drink from the cistern in Bethlehem near the gate!" So the three elite warriors broke through the Philistine forces and drew some water from the cistern in Bethlehem near the gate. They carried it back to David, but he refused to drink it. He poured it out as a drink offering to the Lord

1 Chronicles 14:8-16

When the Philistines heard that David had been anointed king of all Israel, all the Philistines marched up to confront him. When David heard about it, he marched out against them. Now the Philistines had come and raided the Valley of Rephaim. David asked God, "Should I march up against the Philistines? Will you hand them over to me?" The Lord said to him, "March up! I will hand them over to you!" read more.
So they marched against Baal Perazim and David defeated them there. David said, "Using me as his instrument, God has burst out against my enemies like water bursts out." So that place is called Baal Perazim. The Philistines left their idols there, so David ordered that they be burned. The Philistines again raided the valley. So David again asked God what he should do. This time God told him, "Don't march up after them; circle around them and come against them in front of the trees. When you hear the sound of marching in the tops of the trees, then attack. For at that moment the Lord is going before you to strike down the army of the Philistines." David did just as God commanded him, and they struck down the Philistine army from Gibeon to Gezer.