A question has been asked:
"If it is possible to disturb the peace of your dead relatives -no, I
cannot believe it is possible with christian souls. Isaiah 57:2, right?"
This is a very difficult question and I will admit that I don't know the answer. But there is this story in the Bible about King Saul and the witch of Endor who is said to summon Samuel from the dead.
Here is an article I found on this topic:
Our questions about 1 Samuel 28 probably cannot be resolved. The Torah had forbidden necromancy (Deut. 18:9-12).
Moses didn’t say it didn’t “work”; he said it was an abomination. So
the writer of 1 Samuel will truly report that Saul dabbled in
necromancy, but he seems to be stingy with particulars that would
satisfy our curiosity. No overly intricate details. He’s not about to
provide us with a necromancy “how to” kit. Hence I doubt that these
subsidiary queries can ever be definitely answered.
Is the spirit the medium summons actually Samuel? Apparently so,
since what “Samuel” says in vv. 16-19 is entirely consistent with what
he had said prior to his death (see 1 Sam. 15:17-19, 22-23, 28).
(Saul got no “new light” here.) Or could it have been a demon
impersonating Samuel? Some have thought so; others have thought that the
woman screamed because she was actually a phony and not accustomed to
the real thing happening, as it did on this occasion (see Youngblood, in
revised EBC, vol. 3, for various views). Or it could simply be that God
permitted a bona fide manifestation of Samuel through this forbidden
means in order to confirm Saul’s forsakenness to him.
It seems reasonably clear that Samuel is coming from the realm of the dead. Feel free to express your opinion in the comments section:)