Once the Prophet (ﷺ) went through the grave-yards of Medina and heard the voices of two humans who
were being tortured in their graves. The Prophet (ﷺ) said, "They are being punished, but they are not being
punished because of a major sin, yet their sins are great. One of them used not to save himself from
(being soiled with) the urine, and the other used to go about with calumnies (Namima)." Then the
Prophet asked for a green palm tree leaf and split it into two pieces and placed one piece on each
grave, saying, "I hope that their punishment may be abated as long as these pieces of the leaf are not
dried."
Sahih al-Bukhari Book 78, Hadith 85