1 Samuel 23:7-9

And it was told Saul that David was come to Keilah. And Saul said, God hath delivered him into my hand; for he is shut in, by entering into a town that hath gates and bars. And Saul summoned all the people to war, to go down to Keilah, to besiege David and his men. And David knew that Saul was devising mischief against him; and he said to Abiathar the priest, Bring hither the ephod.