Originally Posted by keiv
I believe you're right...
Hazrat Abu Ayub (May Allah be pleased with him) reported: The Messenger of Allah
"He who observes As-Saum (the fasts) in the month of Ramadan, and also observes As-Saum for six days in the month of Shawwal, it is as if he has observed As-Saum for the whole year.''
[Muslim Book 06, Chapter 36, Hadith # 2614].
According to the formula that there is at least ten-fold reward for every virtue in Islam. The Saum of one month (Ramadan) are equivalent to Saum of ten months. If one also observes six days of Saum of Shawwal, they will be equal to Saum of two months. Thus, one becomes eligible for the reward of one full years' Saum. He who makes it a permanent feature is like one who observes Saum throughout his life. He will be considered by Allah as one who observes Saum permanently. Although voluntary in nature, they are highly important.