A man heard another man reciting (in the prayers): 'Say (O Muhammad): "He is Allah, the One." (112.1) And he recited it repeatedly. When it was morning, he went to the Prophet ﷺ and informed him about that as if he considered that the recitation of that Sura by itself was not enough. Messenger of Allah ﷺ said, "By Him in Whose Hand my life is, it is equal to one-third of the Qur'an."
سَمِعَ رَجُلاً يَقْرَأُ {قُلْ هُوَ اللَّهُ أَحَدٌ} يُرَدِّدُهَا فَلَمَّا أَصْبَحَ جَاءَ إِلَى النَّبِيِّ ﷺ فَذَكَرَ لَهُ ذَلِكَ وَكَأَنَّ الرَّجُلَ يَتَقَالُّهَا فَقَالَ رَسُولُ اللَّهِ ﷺ وَالَّذِي نَفْسِي بِيَدِهِ إِنَّهَا لَتَعْدِلُ ثُلُثَ الْقُرْآنِ زَادَ إِسْمَاعِيلُ بْنُ جَعْفَرٍ عَنْ مَالِكٍ عَنْ عَبْدِ الرَّحْمَنِ عَنْ أَبِيهِ عَنْ أَبِي سَعِيدٍ أَخْبَرَنِي أَخِي قَتَادَةُ بْنُ النُّعْمَانِ عَنِ النَّبِيِّ ﷺ