Rectifying Souls:
It is related that Rav Mottele of Chernobyl zy”a would spend every night finding tikkunim for the souls of those who had already left the world and were in need of rectification.
When Rav Mottele once came to a certain city, the chasidim were speaking about him and saying that neshamos came to him at night in search of a tikkun, and he would help them find atonement for their sins so that they no longer had to suffer in the Upper Worlds. There was one misnaged who lived in that city who did not believe it.
He decided to prove them wrong by spying on the Rebbe at night. One night, he successfully snuck into Rav Mottele’s room and hid in the closet. Once everyone else had left the Rebbe alone, the Rebbe closed the door, and the souls of the dead began to come to him and to tell him their problems. When the misnaged heard the Rebbe speaking to the neshamos and giving them tikkunim, he became full of fear and he began to tremble. He was very remorseful for having doubted the Rebbe and for hiding in his room.
He suddenly heard one female neshama that was crying and asking for tikkun, but the Rebbe said, “You never once gave me a penny. How can I give you a tikkun?”
The neshama asked, “What can I do about that now?” Rav Mottele answered, “There is a woman buried next to you in the cemetery who once gave me five silver coins. If she is willing to give you the zechus of one of those coins, I will be able to help you. Go to that neshama and tell her that I sent you.”
“What if she doesn’t believe me?” the neshama asked. Rav Mottele got up and walked over to the closet where the misnaged was hiding. He opened the door and said to him, “Go escort this neshama to the cemetery and say in my name that I am asking the other neshama to give over the zechus of one of the silver coins to her!”
The misnaged ran out of the closet in fear and begged the Rebbe not to make him go. He said, “How can I go to the cemetery in the middle of the night with the soul of a dead person?” The Rebbe told him, “Don’t be afraid. Take my stick with you and you will fly with the neshama to that place and do as I command.” The misnaged asked no more questions and did as he was told.