Sunan Ibn Majah, Volume 5, Book 33, Hadith 3786 (DarusSalam) ⓘ

It was narrated from Abu Hurairah that the Prophet said: "There is a surah in the Qur'an, with thirty verses, which will intercede for its companion (the one who recites it) until he is forgiven: Tabarakal-ladhi bi yadihil mulk (Blessed is He in Whose Hand is the Dominion)."

حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا أَبُو أُسَامَةَ، عَنْ شُعْبَةَ، عَنْ قَتَادَةَ، عَنْ عَبَّاسٍ الْجُشَمِيِّ، عَنْ أَبِي هُرَيْرَةَ، عَنِ النَّبِيِّ ـ صلى الله عليه وسلم ـ قَالَ ‏"‏ إِنَّ سُورَةً فِي الْقُرْآنِ ثَلاَثُونَ آيَةً شَفَعَتْ لِصَاحِبِهَا حَتَّى غُفِرَ لَهُ ‏{تَبَارَكَ الَّذِي بِيَدِهِ الْمُلْكُ}‏ ‏"‏ ‏.‏