Arabic (Original)
حَدَّثَنَا يَحْيَى بْنُ إِسْحَاقَ أَخْبَرَنَا ابْنُ لَهِيعَةَ عَنِ الْحَارِثِ بْنِ يَزِيدَ عَنْ أَبِي الْهَيْثَمِ عَنْ أَبِي سَعِيدٍ الْخُدْرِيِّ قَالَ بَاتَ قَتَادَةُ بْنُ النُّعْمَانِ يَقْرَأُ اللَّيْلَ كُلَّهُ قُلْ هُوَ اللَّهُ أَحَدٌ فَذُكِرَ ذَلِكَ لِلنَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ فَقَالَ النَّبِيُّ عَلَيْهِ السَّلَام وَالَّذِي نَفْسِي بِيَدِهِ لَتَعْدِلُ نِصْفَ الْقُرْآنِ أَوْ ثُلُثَهُ.
English Translation
Yahya ibn Ishaq told us, Ibn Lahi'ah informed us, from al-Harith ibn Yazid, from Abu al-Haytham, from Abu Sa'id al-Khudri, who said: Qatadah ibn al-Nu'man spent the whole night reciting "Say, He is Allah, One." This was mentioned to the Prophet, peace and blessings be upon him, and the Prophet, peace be upon him, said: "By the One in whose hand is my soul, it equals half of the Qur'an, or a third of it."