Ubayy b. Ka'b said: Allah's Messenger (ﷺ) said: O Abu' al-Mundhir, do you know the verse from the Book of Allah which, according to you, is the greatest? I said: Allah and His Apostle (ﷺ) know best. He again said: Abu'l-Mundhir, do you know the verse from the Book of Allah which, according to you, is the greatest? I said: Allah, there is no god but He, the Living, the Eternal. Thereupon he struck me on my breast and said: May knowledge be pleasant for you, O Abu'l-Mundhir!

Ubayy b. Ka'b said: Allah's Messenger (ﷺ) said: O Abu' al-Mundhir, do you know the verse from the Book of Allah which, according to you, is the greatest? I said: Allah and His Apostle (ﷺ) know best. He again said: Abu'l-Mundhir, do you know the verse from the Book of Allah which, according to you, is the greatest? I said: Allah, there is no god but He, the Living, the Eternal. Thereupon he struck me on my breast and said: May knowledge be pleasant for you, O Abu'l-Mundhir!

حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا عَبْدُ الأَعْلَى بْنُ عَبْدِ الأَعْلَى، عَنِ الْجُرَيْرِيِّ، عَنْ أَبِي السَّلِيلِ، عَنْ عَبْدِ اللَّهِ بْنِ رَبَاحٍ الأَنْصَارِيِّ، عَنْ أُبَىِّ بْنِ كَعْبٍ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ يَا أَبَا الْمُنْذِرِ أَتَدْرِي أَىُّ آيَةٍ مِنْ كِتَابِ اللَّهِ مَعَكَ أَعْظَمُ ‏"‏ ‏.‏ قَالَ قُلْتُ اللَّهُ وَرَسُولُهُ أَعْلَمُ ‏.‏ قَالَ ‏"‏ يَا أَبَا الْمُنْذِرِ أَتَدْرِي أَىُّ آيَةٍ مِنْ كِتَابِ اللَّهِ مَعَكَ أَعْظَمُ ‏"‏ ‏.‏ قَالَ قُلْتُ اللَّهُ لاَ إِلَهَ إِلاَّ هُوَ الْحَىُّ الْقَيُّومُ ‏.‏ قَالَ فَضَرَبَ فِي صَدْرِي وَقَالَ ‏"‏ وَاللَّهِ لِيَهْنِكَ الْعِلْمُ أَبَا الْمُنْذِرِ ‏"‏ ‏.‏