Sahih Muslim 7090
صحيح مسلم#7090Sahihحَدَّثَنَا عَاصِمُ بْنُ النَّضْرِ التَّيْمِيُّ، حَدَّثَنَا مُعْتَمِرٌ، قَالَ سَمِعْتُ أَبِي، حَدَّثَنَا قَتَادَةُ، عَنْ أَنَسِ بْنِ مَالِكٍ، أَنَّهُ حَدَّثَ عَنْ رَسُولِ اللَّهِ صلى الله عليه وسلم " إِنَّ الْكَافِرَ إِذَا عَمِلَ حَسَنَةً أُطْعِمَ بِهَا طُعْمَةً مِنَ الدُّنْيَا وَأَمَّا الْمُؤْمِنُ فَإِنَّ اللَّهَ يَدَّخِرُ لَهُ حَسَنَاتِهِ فِي الآخِرَةِ وَيُعْقِبُهُ رِزْقًا فِي الدُّنْيَا عَلَى طَاعَتِهِ " .
Anas b. Malik reported that Allah's Messenger (ﷺ) thus told him:When a non-believer does good he is made to taste Its reward in this world. And so far as the believer is concerned, Allah stores (the reward) of his virtues for the Hereafter and provides him sustenance in accordance with his obedience to Him
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
Every narration in Sahih Muslim is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 52:44