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.
أَنَّهُ أَخْبَرَهُ أَنَّ قُلْ هُوَ اللَّهُ أَحَدٌ تَعْدِلُ ثُلُثَ الْقُرْآنِ وَأَنَّ تَبَارَكَ الَّذِي بِيَدِهِ الْمُلْكُ تُجَادِلُ عَنْ صَاحِبِهَا