Abu Hurayrah (may Allah be pleased with him) reported: The Prophet (may Allah's peace and blessings be upon him) said: "There is a Sūrah in the Qur’an consisting of thirty verses. It interceded for a man until he was forgiven. It is: {Blessed is He in Whose hand is the dominion.} [Sūrat al-Mulk].” In another narration by Abu Dawūd: “It intercedes.”
The Messenger of Allah (may Allah's peace and blessings be upon him) informs us in this Hadīth that the Qur’an has a 30-verse Sūrah that interceded for a man until Allah, the Almighty, forgave him. As he used to recite this Sūrah regularly during his lifetime, it interceded for him after his death, until Allah, the Almighty, averted His punishment from him. The Prophet (may Allah's peace and blessings be upon him) did not name the Sūrah at the beginning of the Hadīth, but he did so at its end; a powerful indication of its sublimity and high rank and a greater motive for reciting it persistently.