1 Samuel 28:6-10

So Saul inquired of the Lord, but the Lord did not answer him, either in dreams, or by the Urim, or by the prophets.

Then Saul said to his servants, “Find for me a woman who is a medium, so that I may go to her and inquire of her.” And his servants said to him, “Behold, there is a woman who is a medium at En-dor.”

Then Saul disguised himself by putting on different clothes, and went, he and two men with him, and they came to the woman by night; and he said, “Consult the spirit for me, please, and bring up for me the one whom I shall name for you.”

But the woman said to him, “Behold, you know what Saul has done, that he has eliminated the mediums and spiritists from the land. Why are you then setting a trap for my life, to bring about my death?”

So Saul swore an oath to her by the Lord, saying, “As the Lord lives, no punishment shall come upon you for this thing.”