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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
ahmad:22191 – ʿAlī b. Isḥāq > ʿAbdullāh b. al-Mubārak > Yaḥyá b. Ayyūb > ʿUbaydullāh b. Zaḥr > ʿAlī b. Yazīd > al-Qāsim > Abū Umāmah

[Machine] The Prophet ﷺ said, "Allah said, 'The most beloved thing with which My servant worships Me is sincerity and loyalty to Me.'"  

أحمد:٢٢١٩١ – حَدَّثَنَا عَلِيُّ بْنُ إِسْحَاقَ أَخْبَرَنَا عَبْدُ اللهِ بْنُ الْمُبَارَكِ أَخْبَرَنَا يَحْيَى بْنُ أَيُّوبَ عَنْ عُبَيْدِ اللهِ بْنِ زَحْرٍ عَنْ عَلِيِّ بْنِ يَزِيدَ عَنِ الْقَاسِمِ عَنْ أَبِي أُمَامَةَ

عَنِ النَّبِيِّ ﷺ قَالَ قَالَ اللهُ أَحَبُّ مَا تَعَبَّدَنِي بِهِ عَبْدِي إِلَيَّ النُّصْحُ لِي  

See similar narrations below:

Collected by Suyūṭī