Volume 3, Book 31, Number 196:
Narrated ‘Abdullah bin ‘Amr bin Al-‘As:
Allah’s Apostle said to me, “O ‘Abdullah! Have I not been informed that you fast during the day and
offer prayers all the night.” ‘Abdullah replied, “Yes, O Allah’s Apostle!” The Prophet said, “Don’t do
that; fast for few days and then give it up for few days, offer prayers and also sleep at night, as your
body has a right on you, and your wife has a right on you, and your guest has a right on you. And it
is sufficient for you to fast three days in a month, as the reward of a good deed is multiplied ten
times, so it will be like fasting throughout the year.” I insisted (on fasting) and so I was given a hard
instruction. I said, “O Allah’s Apostle! I have power.” The Prophet said, “Fast like the fasting of the
Prophet David and do not fast more than that.” I said, “How was the fasting of the Prophet of Allah,
David?” He said, “Half of the year,” (i.e. he used to fast on every alternate day).
Afterwards when ‘Abdullah became old, he used to say, “It would have been better for me if I had
accepted the permission of the Prophet (which he gave me i.e. to fast only three days a month).”