The Messenger of Allah ﷺ said, "By the One in whose hand is Muhammad's soul, the breath of the fasting person is more fragrant to Allah than the scent of musk."
حدثنا يزيد أخبرنا محمد عن موسى بن يسار
قال رسول الله ﷺ والذي نفس محمد بيده لخلوف فم الصائم أطيب عند الله من ريح المسك
Its chain of transmission is sahih. Part of its meaning has already appeared at 7194, but Abu Hurairah related it here as if it were two separate hadiths, so we have repeated the number for the second one, indicating the repetition by writing the letter "m" next to it.7485m - He said, the Messenger of Allah said, "Allah, Mighty and Sublime, says, 'Every deed of the son of Adam is his, except fasting, which is Mine, and I reward for it. He gives up his food and drink only for My sake, so his fasting is for Me and I reward for it. Every good deed is multiplied tenfold, up to seven hundred times, except fasting, which is Mine, and I reward for it.'"Sahih (7485m). It is sahih, on the strength of the same chain given previously. We noted at 7194 that this is a hadith qudsi, though the text there did not explicitly state its attribution to Allah, Mighty and Sublime, even though that was clear from the wording's context. Here, however, it is explicit in that regard.Muslim related, at 316-317, something similar in meaning, at greater length, through the route of Amash, from Abu Salih, from Abu Hurairah.In the wording of the hadith here, his statement is, "so his fasting is for Me and I reward for it." This is how it is established in the three original manuscripts. I consider this to be an oversight on the part of the early copyists, since the context requires it to be "so his fasting is for Me" instead of "his fasting is his," which is what is established in all the narrations of the hadith. In the margin of manuscript K, the word "to" was written, with a mark above it that I could not determine whether it was a mark of correctness or a mark indicating a variant reading.