Question: I am a young man and I used to observe Sawm (Fast) similar to the Sawm of Daawood (David, peace be upon him). However, someone told me that if the day to observe Sawm falls on a Saturday or Friday, it should not be observed without a day before or after. He said that this is the opinion of Shaykh Al-Albaanee (may Allaah be merciful to him). I have continued observing Sawm although I am still confused.
Please advise me on the ruling of observing Sawm on Saturday or Friday without observing the Sawm of a day before or after or if it happens to coincide with the Day of `Arafah (9th of Dhul-Hijjah) or the Day of `Aashooraa’ (10th of Muharram)?
Answer: It is permissible for the one who observes the Sawm of Daawood (peace be upon him) to observe Sawm on Friday or Saturday alone without a day before or after. This ruling also applies to the Day of `Arafah and `Aashooraa’. It should be known that the Hadeeth which states that Sawm on Saturday is forbidden except in case of obligatory Sawm is not Saheeh (authentic)… read more here.