NASAI-KUBRA 2539:
from Abū Hurayrah —
Allah, the Majestic and the Exalted, said: Every act of the son of Adam is for him except fasting. It is done for My sake, and I will give a reward for it. By Allah in Whose Hand is the life of Muhammad, the breath of the observer of fast is sweeter to Allah than the fragrance of musk. (Using translation from Muslim 1151b)
الكبرى للنسائي ٢٥٣٩:
عن ابو هريره —
سَمِعْتُ رَسُولَ اللهِ ﷺ يَقُولُ قَالَ اللهُ كُلُّ عَمَلِ ابْنِ آدَمَ لَهُ إِلَّا الصِّيَامُ هُوَ لِي وَأَنَا أَجْزِي بِهِ وَالَّذِي نَفْسُ مُحَمَّدٍ بِيَدِهِ لَخُلْفَةُ فَمِ الصَّائِمِ أَطْيَبُ عِنْدَ اللهِ مِنْ رِيحِ الْمِسْكِ
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