What do the scholars and experts of shari’ah say regarding a person who fasts on the day of ‘Ashura but does not fast on the 9th? Will it suffice to fast on the 11th of Muharram instead?
It is mustahab to fast on the 11th of Muharram if one has only kept the ‘Ashura fast and missed the 9th.
Shaykh al-Islam Zakariyya al-Ansari has mentioned in ‘Asna al-Matalib Sharh Rawd al-Talib’: “If one has not kept the fast of the 9th of Muharram along with the ‘Ashura fast then it is mustahab for him to fast on the 11th. Imam Shafi’i has stated in his works such as ‘Al-Umm’ and ‘Al-Imla’ that it is mustahab to keep a fast of three days. This has also been mentioned by Shaykh Abu Hamid and various scholars. The narration of Imam Ahmad also reflects this, “Fast the day of ‘Ashura and differentiate from the Jews by fast a day before and after.”
Allah ﷻ knows best
This fatwa is written by Dr. Hafiz Muhammad Munir Al-Azhari