for the sake of worshipping Allah, rather than for some physical or worldly benefit, but in order to draw nearer to Allah through acts of worship.
These three days suffice in place of fasting three days of every month, concerning which the Prophet, peace and blessings be upon him, said: “Fasting three days of every month is like fasting for a lifetime.” (1) This is because a good deed is multiplied tenfold: three days thus count as thirty days for one month, and likewise for the second and third months, so it is as though one had fasted the entire year. The Prophet, peace and blessings be upon him, used to fast three days of every month. Aisha said: “He did not mind whether he fasted them at the beginning of the month, its middle, or its end.” (2) The Prophet, peace and blessings be upon him, also instructed three of his Companions to observe them: Abu Hurayrah, Abu al-Darda, and Abu Dharr. (3)
Thus, we have two matters:
The first: It is recommended to fast three days of every month, whether they are at the beginning, middle, or end of the month, and whether they are consecutive or separate.
The second: The fasting should be observed on the White Days.