Language:
كتاب بدء الخلق
59  
Beginning of Creation
(1)
Chapter: The Statement of Allah Taa'la: "And He it is Who originates the creation; then will repeat it and this is easier for Him..."
(1)
بَابُ مَا جَاءَ فِي قَوْلِ اللَّهِ تَعَالَى: {وَهُوَ الَّذِي يَبْدَأُ الْخَلْقَ ثُمَّ يُعِيدُهُ}
Sahih al-Bukhari 3194

Narrated Abu Huraira:

Allah's Messenger (ﷺ) said, "When Allah completed the creation, He wrote in His Book which is with Him on His Throne, "My Mercy overpowers My Anger."

حَدَّثَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، حَدَّثَنَا مُغِيرَةُ بْنُ عَبْدِ الرَّحْمَنِ الْقُرَشِيُّ، عَنْ أَبِي الزِّنَادِ، عَنِ الأَعْرَجِ، عَنْ أَبِي هُرَيْرَةَ ـ رضى الله عنه ـ قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏ "‏ لَمَّا قَضَى اللَّهُ الْخَلْقَ كَتَبَ فِي كِتَابِهِ، فَهْوَ عِنْدَهُ فَوْقَ الْعَرْشِ إِنَّ رَحْمَتِي غَلَبَتْ غَضَبِي ‏"‏‏.‏
Reference : Sahih al-Bukhari 3194
In-book reference : Book 59, Hadith 5
USC-MSA web (English) reference : Vol. 4, Book 54, Hadith 416
  (deprecated numbering scheme)