Forgetting the Qur'an. And can one say: “I forgot such and such a Verse? Sahih al-Bukhari 5037b
Arabic hadith text
حَدَّثَنَا مُحَمَّدُ بْنُ عُبَيْدِ بْنِ مَيْمُونٍ، حَدَّثَنَا عِيسَى، عَنْ هِشَامٍ، وَقَالَ، أَسْقَطْتُهُنَّ مِنْ سُورَةِ كَذَا. تَابَعَهُ عَلِيُّ بْنُ مُسْهِرٍ وَعَبْدَةُ عَنْ هِشَامٍ
Translation
Narrated Hisham
(The same Hadith as 6.556, adding): which I missed (modifying the Verses).