1 Samuel 28:12
And when the woman saw Samuel, she cried with a loud voice: and the woman spake to Saul, saying, Why hast thou deceived me? for thou art Saul. And when the woman saw Samuel, she cried with a loud voice: and the woman spake to Saul, saying, Why hast thou deceived me? for thou art Saul.
The verse takes place as the Philistine army gathered for battle, when Saul felt alone and defenseless because God had forsaken him. He had come to the woman of Endor in disguise to conceal his identity as king. When the woman saw the apparition she identified as Samuel, she cried out with a loud, startled voice, recognized her visitor as Saul, and accused him of deceiving her, showing she understood the encounter as dangerous and feared the consequences.
The figure was not the real Samuel and was not a message from God, but a satanic counterfeit produced by Satan through the sorceress. Her incantations did not summon God's prophet from the dead, for God did not bring Samuel back from the grave, and Saul was consulting a familiar spirit rather than communicating with God's prophet. Satan's angels can impersonate the dead, and the evil spirit impersonating Samuel secretly warned the woman that her visitor was Saul. Her recognition and words were therefore prompted by that spirit, and her cry and recognition were part of Satan's deception.
Through the impersonation Satan spoke accurately about Saul's fate, giving a correct description and correct statement of his end and doom. He could do so because he knew Samuel, and this accuracy made the deception more convincing while he exulted in Saul's confusion. He had led Saul as a willing captive step by step away from God until his perceptions were blunted, first insinuating himself into Saul's favor in a plausible, cautious manner and leading him almost imperceptibly into crime, then once Saul was fully in his snare revealing his end to him. Satan used the prediction of doom through the woman to draw rebellious Israel into trusting the sorceress, turning from God as their counselor and seeking knowledge God had withheld, so that by being instructed by his satanic cunning they would sever the last link holding them to God.
The dead do not know or communicate with the living, and Satan misleads people by appearing under the guise of departed friends and using the guise of the dead. The mystic voice at Endor belongs to the deceptive work of sorcery like modern Spiritualism, through which evil spirits deceive people and gain influence over minds.