Is fasting Thursday and Monday every week equal to fasting the whole year?
All perfect praise be to Allaah, the Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
Undoubtedly, fasting Mondays and Thursdays is a recommended act of Sunnah, and the Hadeeths support this fact. It was narrated on the authority of Abu Hurayrah that the Prophet, sallallaahu ‘alayhi wa sallam, said: "Man's records of deeds are submitted every Monday and Thursday, and I like my deeds to be submitted while I am fasting." [At-Tirmithi]
There is no text, to the best of our knowledge, that fasting Mondays and Thursdays specifically equals to fasting the whole year. However, it was reported that fasting three days every month is like fasting the whole year. The Prophet, sallallaahu ‘alayhi wa sallam, said to ‘Abdullaah ibn ‘Amr ibn Al-‘Aas : "Fast three days every month, since a good deed is multiplied ten times, so this would be like fasting for the whole year." [Al-Bukhari and Muslim]
Thus, fasting one day equals fasting ten days, and fasting three days equals fasting the whole month (thirty days). Hence, when the Muslim fasts three days every month, he is considered to have observed fasting of the whole year. In that way, it could be assumed that the Muslim who observes this fasting every month is expected to win this reward.
And Allaah Knows best.
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