The Book of Purification (Kitab Al-Taharah)

Muslim :: Book 2 : Hadith 575

Ibn Abbas reported: The Messenger of Allah (may peace be upon him) happened to pass by two graves and said: They (their occupants) are being tormented, but they are not tormented for a grievous sin. One of them carried tales and the other did not keep himself safe from being defiled by urine. He then called for a fresh twig and split it into two parts, and planted them on each grave and then said: Perhaps, their punishment way be mitigated as long as these twigs remain fresh.

Source materials are from the University of Southern California MSA site
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