1 Samuel 28:1-7

And it came to pass in those days, that the Philistines gathered their hosts together for warfare, to fight with Israel. And Achish said unto David, Know thou assuredly, that thou shalt go out with me in the host, thou and thy men. And David said to Achish, Therefore thou shalt know what thy servant will do. And Achish said to David, Therefore will I make thee keeper of my head for ever. Now Samuel was dead, and all Israel had lamented him, and buried him in Ramah, even in his own city. And Saul had put away those that had familiar spirits, and the wizards, out of the land. And the Philistines gathered themselves together, and came and encamped in Shunem: and Saul gathered all Israel together, and they encamped in Gilboa. And when Saul saw the host of the Philistines, he was afraid, and his heart trembled greatly. And when Saul inquired of Jehovah, Jehovah answered him not, neither by dreams, nor by Urim, nor by prophets. Then said Saul unto his servants, Seek me a woman that hath a familiar spirit, that I may go to her, and inquire of her. And his servants said to him, Behold, there is a woman that hath a familiar spirit at En-dor.