The Messenger of Allah ﷺ said, "Allah says, 'Fasting is for Me, and I am the One who rewards it. He gives up his food, his drink, and his desire for My sake.' Fasting is a shield, and the one who fasts has two moments of joy, a joy when he breaks his fast and a joy when he meets Allah
. The breath of the fasting person is more pleasing to Allah than the fragrance of musk."
حدثنا أبو نعيم قال حدثنا الأعمش عن أبي صالح
قال رسول الله ﷺ يقول الله عز وجل الصوم لي وأنا أجزي به يدع طعامه وشرابه وشهوته من أجلي فالصوم جنة وللصائم فرحتان فرحة حين يفطر وفرحة حين يلقى الله عز وجل ولخلوف فيه أطيب عند الله من ريح المسك
A sahih chain. It was previously mentioned in , part of it as a qudsi hadith and part of it as a hadith of the Prophet. Bukhari narrated it in 9/175, in the Book of Tawhid, on the saying of Allah Most High, "They want to change Allah's words" [Fath 48:15], as did Nasai in the Book of Fasting, and Tabarani in Al-Kabir 10/158, no. 10198.