“One of the companions of the Prophet [Muhammad] set up a tent on a grave while not aware that it was a grave. The man heard the person within the grave reciting Surat Al-Mulk until it was completed. So the man came to the Nabi and informed him of what occurred. The Nabi said, “It is a prevention! It is a salvation saving one from the punishment of the grave!”
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This is not authentic.

Muhammad ibn Abdul Malik ibn Abish-Shawarib>>Yahya ibn ‘Amru ibn Malik An-Nukri>>from his father>>from Abil Jawzaa’>>Ibn ‘Abbas (radiya Allahu anhu) who said,