Sayyiduna Abu Hurayrah (may Allah be pleased with him) narrates that the Messenger of Allah (peace and blessings be upon him) said: "Allah Almighty says: Fasting is for Me and I Myself will give its reward, for he gives up his desire and leaves his eating and drinking for My sake. Fasting is a shield, and the fasting person has two joys: one joy at the time of breaking the fast and the other at the time of meeting his Lord. And the smell of his mouth is more pleasant to Allah than the fragrance of musk."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / 8331