Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) narrates: One of the Companions of the Prophet (peace and blessings be upon him) pitched his tent over a grave without knowing that it was a grave, and suddenly (he heard the voice of) a person reciting Surah Tabarak al-Mulk until he completed it. He came to the Prophet (peace and blessings be upon him) and said: "O Messenger of Allah, I pitched my tent over a grave without knowing that it was a grave, and suddenly (I heard the voice of) a person reciting Surah Tabarak (al-Mulk) until he completed it." The Messenger of Allah (peace and blessings be upon him) said: "It is the protector; it is the saviour; it saves him from the punishment of the grave."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 12746