NET
50 David prevailed over the Philistine with just the sling and the stone. He struck down the Philistine and killed him. David did not even have a sword in his hand.
Darby
50 So David overcame the Philistine with a sling and a stone, and smote the Philistine and killed him; and there was no sword in the hand of David.
KJV
50 So David prevailed over the Philistine with a sling and with a stone, and smote the Philistine, and slew him; but [there was] no sword in the hand of David.