The Messenger of Allah said to me: Read the Qur’an in a month. I said: I can tolerate more than that, and I kept asking him until he said: Read the Qur’an in five days, and fast three days of the month. I said: I can endure more than that. He said: So fast the most beloved fasting to Allah; the fasting of David (PBUH). He used to fast one day and break his fast the next.

My intimate friend -the prophet (PBUH)- exhorted me of three deeds: Praying the witr (odd/single rak'ah) before bed, praying two rak'ahs of Duha, and fasting three days every month.

The Messenger of Allah (PBUH) said to me: I have been informed that you fast during the day and stay up all night -praying, so do not do that. Your body has its own share in you, your eyes have its own share in you, and your wife has her own share in you. Fast three days of every month, and that is fasting for a lifetime. 'Abdullah said: I have strength. The Prophet (PBUH) said: Fast, the fasting of David (PBUH). Fast one day and break your fast the next.

The Messenger of Allah (PBUH) used to fast three days of every month. Mu'azthah asked: Which were they? 'A'ishah replied: It didn't matter to him which days they were.

Fasting three days of every month, is the fasting and breaking the fast for lifetime.