The first and the greatest is what the messenger of Allah (May the blessings and peace of Allah be upon him) mentioned, he said:
"Whoever fasts Ramadan then he follows it by fasting six days of Shawwal, it is as if he fasts the whole age."
The age means the whole year.
One can fast the six days consecutively, he can also fast them separately.
He should only fast them during the month, after that, there is a minimum and a maximum for optional fasting.
Imam Abul-Aza'em (May Allah be pleased with him) mentioned this and said:
"The maximum limit for optional fasting is to fast day after day and this is the fasting of Prophet David (Dawood) (peace be upon him)."
When our master Abdullah Ibn-Omar (May Allah be pleased with him) fasted the whole year, the messenger of Allah said to him:
"Fast day after day, this is the fasting of Prophet David (Dawood) (Peace be upon him) and it is the best fasting. He said: I can afford better than this. The prophet (May the blessings and peace of Allah be upon him) said: Nothing is better than this."
These are the words of the messenger of Allah. The middle limit is to fast Monday and Thursday weekly, the prophet used to do this at the beginning of his call, he said:
"The deeds are shown on Mondays and Thursdays, I like my deed to be shown while I am fasting."
At the end of his life when he got older, and in order to give example for the weak and the ill people, the prophet used to fast three days a month, and this is the minimum limit, the messenger of Allah (May the blessings and peace of Allah be upon him) said about this:
"Fasting three days a month and fasting Ramadan to Ramadan are like fasting the whole age."
So Imam Abul-Aza'em said: "A follower shouldn’t do less than this."
I.e. he shouldn’t fast less than three days a month, he can fast Monday or Thursday weekly or fast them consecutively, he should fast 3 days a month. The most important thing is to keep on doing this not to do one year and leave it all his age after that without having excuses.
As for youths, a faithful young man should fast Mondays and Thursdays weekly or fast day after day especially for single young men, at least he should fast Mondays and Thursdays, but it is better for him to fast day after day because it is the recommendation of the beloved, he said:
"Oh young people, he who is able financially and physically to marry, he should marry because marriage will make him lower his sights and protect his private parts. He who can not marry, he should fast because fasting will be a protection for him."
Protection means guarding, should he only fast three days a month? No, he should fast Mondays and Thursdays or fast day after day. Or he can fast Mondays and Thursdays and also three days a month, the thirteenth, the fourteenth and the fifteenth of every lunar month, this is the minimum limit for the youths. Those who have excuses, they should keep to fasting three days a month, because this is what the messenger of Allah kept doing and we should do as Allah says:
33-21: "The messenger of GOD has set up a good example for those among you who seek GOD and the Last Day, and constantly think about GOD."
 It was narrated after Abi-Ayoob in Saheeh Al-Imam Muslim (May Allah be pleased with him).
 It was narrated after Abdullah Ibn-Omar (May Allah be pleased with him) in Saheeh Al-Bukhary.
 It was narrated after Abi-Horayrah takhreej Al-Meshkat in Atta'leek in Attargheeb and Al-Irwaa.
 It was narrated in Saheeh Muslim after Abi-Katadah, the completion is: Fasting the day of Arafat (the ninth day of Dhul-Hajja) expiates the previous year and the remaining year, and fasting the day of Ashouraa (the tenth day of Muharram) expiates the sins committed in the last year.
 It was narrated after Abdullah Ibn-Masood, (May Allah be pleased with him) narrated by Al-Bukhary and the rest of the six books.
اعلان في الاسفل
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