The Summoning of the Dead
In old times, a man named Hannikel lived in Eßbach. He was able to summon the dead, and indulged in sacrilegious traffic with them in order to reveal thefts with their aid or to discover what would occur in the future. When he wanted to learn things of this type, he secretly took the pick used by the undertaker which was used to dig up the graves. Then, between 11 and 12 o’clock at night, he walked to the church through the graveyard. There, he carved three crosses into the church door. Then he stood on the grave of a deceased person he had known in life, and called the latter by name three times.
The dead person, who had been woken up by this, now asked what Hannikel wanted, and revealed everything that he wanted to know — but added: “But leave me in peace from now on.”
Then the summoner had to refrain from uttering even a single word, and had to leave this site without looking back. Otherwise, the dead — who threw stones all around him — would have hit him and killed him.
He did not escape his punishment. One day, and merely by accident, he turned around for a tiny bit. And then they stoned him in such a manner that he died of his injuries three days later.
Source: Bechstein - Thüringer Sagenbuch Zweiter Band, p. 155