Abu Huraira reported: The Messenger of Allah, peace and blessings be upon him, said, “By the One in whose hand is my soul, the odor coming from the mouth of a fasting person is more pleasant to Allah Almighty than the scent of musk. Allah said: He leaves his food, his drink, and his passions for My sake. The fast is for Me and I will reward him for it with a good deed ten times like it.”
Source: Ṣaḥīḥ al-Bukhārī 1894
Grade: Sahih (authentic) according to Al-Bukhari
عَنْ أَبِي هُرَيْرَةَ قَالَ قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ وَالَّذِي نَفْسِي بِيَدِهِ لَخُلُوفُ فَمِ الصَّائِمِ أَطْيَبُ عِنْدَ اللهِ تَعَالَى مِنْ رِيحِ الْمِسْكِ وَقَالَ اللَّهُ يَتْرُكُ طَعَامَهُ وَشَرَابَهُ وَشَهْوَتَهُ مِنْ أَجْلِي الصِّيَامُ لِي وَأَنَا أَجْزِي بِهِ وَالْحَسَنَةُ بِعَشْرِ أَمْثَالِهَا
1894 صحيح البخاري كتاب الصوم باب فضل الصوم