“A man came to the Prophet [saws] and said, ‘O Messenger of Allah! How do you fast?’ The Messenger of Allah [saws] got angry at what he said. When ‘Umar [ra] observed this he said, “We are satisfied with Allah [swt] as our Lord Islam as our religion and Muhammad [saws] as our Prophet. We seek refuge in Allah [swt] from the anger of Allah [swt] and the anger of His Messenger.’ Umar [ra] kept on repeating these words until the anger of the Prophet [saws] receded. He then said, ‘O Messenger of Allah [saws]! What about a person who fasts continuously?’ He said, ‘He is neither fasting nor breaking fast.’ He said, ‘O Messenger of Allah [saws]! What about a person who fasts two days and does not fast one day?’ He said, ‘Is there anybody who can do that?’ He said, ‘O Messenger of Allah [saws]! What about a person who fasts for a day and breaks his fast for a day?’ He said, ‘That is the fast of Dawud [as].’ He said, ‘O Messenger of Allah [saws]! What about a person who fasts for a day and breaks his fast for two days?’ He said, ‘I wish I could do that.’ Then the Messenger of Allah [saws] said, ‘[Fasting] three days from every month and Ramadan to Ramadan this is fasting all the time. And fasting the day of ‘Arafah; I hope from Allah [swt] that it may expiate for [the sins of] the preceding and the following year. And fasting the day of ‘Ashura’; I hope from Allah [swt] that it may atone for the sins of the preceding year.’”[79]
First Monday and Thursday, second Thursday
“One of the wives of the Prophet [saws] said, ‘The Prophet [saws] used to fast on the day of ‘Ashura’, nine days of Dhul-Hijjah and three days of each month: the first Monday of the month and two Thursdays.’”[80]
“The Messenger of Allah [saws] used to fast three days of each month: the first Monday of the month, then Thursday, then the following Thursday.”[81]
First Monday and Thursday, second Monday
“The Messenger of Allah [saws] used to fast three days of every month: the Monday and Thursday of the first week and the Monday of the following week.”[82]
First Thursday, second Monday, third Monday
“The Messenger of Allah [saws] used to enjoin fasting three days: the first Thursday, and Monday and Monday.”[83]
The days of Al-Bidh
“O Abu Dharr [ra]! When you fast three days out of a month then fast the thirteenth fourteenth and fifteenth.”[84]
“Fasting three days of each month is fasting for a lifetime and the shining days of Al-Bidh, the thirteenth fourteenth and fifteenth.”[85]