Abu Hurairah (RA) said: “I heard the Messenger of Allah ﷺ say: ‘Allah, the Mighty and Sublime, said: Every deed of the son of Adam is for him, except fasting; it is for Me and I shall reward for it.’ By the One in Whose hand is the soul of Muhammad, the smell coming from the mouth of the fasting person is better before Allah than the fragrance of musk.” (Sahih)