1 Samuel 23:7 (KJV)

So David and his men went to Keilah, and fought with the Philistines, and brought away their cattle, and smote them with a great slaughter. So David saved the inhabitants of Keilah.

And it came to pass, when Abiathar the son of Ahimelech fled to David to Keilah, that he came down with an ephod in his hand.

And it was told Saul that David was come to Keilah. And Saul said, God hath delivered him into mine hand; for he is shut in, by entering into a town that hath gates and bars.

And Saul called all the people together to war, to go down to Keilah, to besiege David and his men.

And David knew that Saul secretly practised mischief against him; and he said to Abiathar the priest, Bring hither the ephod.