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Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
ibnmajah:189 – Muḥammad b. Yaḥyá > Ṣafwān b. ʿĪsá > Ibn ʿAjlān from his father > Abū Hurayrah

"The Messenger of Allah said: 'Your Lord wrote for Himself with His Own Hand before He created the creation: "My mercy precedes My wrath."  

ابن ماجة:١٨٩ – حَدَّثَنَا مُحَمَّدُ بْنُ يَحْيَى حَدَّثَنَا صَفْوَانُ بْنُ عِيسَى عَنِ ابْنِ عَجْلاَنَ عَنْ أَبِيهِ عَنْ أَبِي هُرَيْرَةَ قَالَ

قَالَ رَسُولُ اللَّهِ ﷺ كَتَبَ رَبُّكُمْ عَلَى نَفْسِهِ بِيَدِهِ قَبْلَ أَنْ يَخْلُقَ الْخَلْقَ رَحْمَتِي سَبَقَتْ غَضَبِي  

See similar narrations below:

Collected by Tirmidhī, Suyūṭī
tirmidhi:3543 – Qutaybah > al-Layth > Ibn ʿAjlān from his father > Abū Hurayrah

“Verily, Allah when He created the creation, He wrote with His Hand concerning Himself, that: ‘My mercy prevails over My wrath.’”  

Abū ʿĪsá said that this Ḥadīth is Ḥasan-Ṣaḥīḥ-Gharīb.
الترمذي:٣٥٤٣ – حَدَّثَنَا قُتَيْبَةُ حَدَّثَنَا اللَّيْثُ عَنِ ابْنِ عَجْلاَنَ عَنْ أَبِيهِ عَنْ أَبِي هُرَيْرَةَ

عَنْ رَسُولِ اللَّهِ ﷺ قَالَ إِنَّ اللَّهَ حِينَ خَلَقَ الْخَلْقَ كَتَبَ بِيَدِهِ عَلَى نَفْسِهِ إِنَّ رَحْمَتِي تَغْلِبُ غَضَبِي  

قَالَ أَبُو عِيسَى هَذَا حَدِيثٌ حَسَنٌ صَحِيحٌ غَرِيبٌ