Ubayy ibn Ka’b reported: The Messenger of Allah, peace and blessings be upon him, said, “O Abu Mundhir, do you know which verse in the Book of Allah with you is greatest?” I recited, “Allah! There is no God worthy of worship except Him, the Ever-Living, All-Sustaining,” (2:255). The Prophet struck me on the chest, saying, “By Allah, O Abu Mundhir, rejoice in this knowledge!”
Source: Ṣaḥīḥ Muslim 810
Grade: Sahih (authentic) according to Muslim
عَنْ أُبَيِّ بْنِ كَعْبٍ قَالَ قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يَا أَبَا الْمُنْذِرِ أَتَدْرِي أَيُّ آيَةٍ مِنْ كِتَابِ اللَّهِ مَعَكَ أَعْظَمُ قَالَ قُلْتُ اللَّهُ لَا إِلَهَ إِلَّا هُوَ الْحَيُّ الْقَيُّومُ قَالَ فَضَرَبَ فِي صَدْرِي وَقَالَ وَاللَّهِ لِيَهْنِكَ الْعِلْمُ أَبَا الْمُنْذِرِ
810 صحيح مسلم كتاب صلاة المسافرين وقصرها باب فضل سورة الكهف وآية الكرسي
