Sayyiduna Abu Hurayrah (may Allah be pleased with him) narrates that the Prophet (peace and blessings be upon him) said: "Allah Almighty says: 'Fasting is for Me, and I will give the reward for it.'
(The narrator says:) By the oath of the Prophet (peace and blessings be upon him): "The smell of the fasting person's mouth is purer in the sight of Allah Almighty than the fragrance of musk. Whoever of you begins the morning fasting should neither speak obscenely nor behave ignorantly. If someone quarrels with him, he should say: 'I am fasting.' For on the Day of Resurrection there will be a Pond for them, and no one but those who fast will come to that Pond."
(Allamah al-Haythami says:) I say:
This report is mentioned in the Sahih, but in abridged form, in which only the Pond is mentioned.
Al-Bazzar recorded it, and its narrators have been declared trustworthy.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الصيام / 5093