Muwatta Malik, Book 15, Hadith 491 (In-Book) ⓘ
Yahya related to me from Malik from Ibn Shihab that Humayd ibn Abd ar-Rahman ibn Awf had told him that Surat al-Ikhlas (Sura 112) was equal to a third of the Qur'an, and that Surat al-Mulk (Sura 67) pleaded for its owner.
وَحَدَّثَنِي عَنْ مَالِكٍ، عَنِ ابْنِ شِهَابٍ، عَنْ حُمَيْدِ بْنِ عَبْدِ الرَّحْمَنِ بْنِ عَوْفٍ، أَنَّهُ أَخْبَرَهُ أَنَّ {قُلْ هُوَ اللَّهُ أَحَدٌ} تَعْدِلُ ثُلُثَ الْقُرْآنِ وَأَنَّ {تَبَارَكَ الَّذِي بِيَدِهِ الْمُلْكُ} تُجَادِلُ عَنْ صَاحِبِهَا .
also referenced under: Book 15, Hadith 19 (USC-MSA)