The Book of Fasting (Kitab Al-Sawm)

Muslim :: Book 6 : Hadith 2614

Abu Ayyub al-Ansari (Allah be pleased with him) reported Allah's Messenger (may peace be upon him) as saying: He who observed the fast of Ramadan and then followed it with six (fasts) of Shawwal. it would be as if he fasted perpetually.

Source materials are from the University of Southern California MSA site
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