John Gill Commentary 1 Samuel 23:5

"And David and his men went to Keilah, and fought with the Philistines, and brought away their cattle, and slew them with a great slaughter. So David save the inhabitants of Keilah." — 1 Samuel 23:5 (ASV)

So David and his men went to Keilah
Animated by a commission from God, and a promise of success by him:

and fought with the Philistines ;
encamped before Keilah:

and brought away their cattle ;
which they had brought with them for the support of their army; or having routed them, they pursued them into their own country, and brought off their cattle from thence:

and smote them with a great slaughter ;
killed great numbers of them, and put the rest to flight:

so David saved the inhabitants of Keilah ;
from falling into the hands of the Philistines, by timely raising the siege of the city.