[left that other site]

Demons have the demonstrated capability of pretending convincingly to be anyone. Saul knew/perceived/supposed/presumed/expected/hoped this was Samuel, but I’ve always been skeptical, particularly considering the scarcity of similar events recorded in Scripture.

I agree.

[Hebrews 11:6]

Offhand, I recall only these other manifestations from beyond the grave:

* Jesus' resurrection, of course--absolutely one-of-a-kind

* Moses and Elijah on the Mount of Transfiguration, which may have been commonplace to Jesus but which the apostles saw on this single occasion (although Elijah had not actually died and, as I have argued elsewhere, neither had Moses)

* various people raised from the dead, but this is different-in-kind, because they quickly returned fully to life without their spirits being consulted in the meantime

* Moses in Jesus' parable about Lazarus and the unmerciful rich man; but context suggests this parable was plainly His invention and not a report