What are the days on which it is prohibited to observe Sawm (Fast)?
The days on which it is prohibited to observe Sawm include the day of doubt which is the thirtieth day of the month of Sha`ban if the new moon of Ramadan has not been sighted, the two Eids: `Eid-ul-Fitr (the Festival of Breaking the Fast) and `Eid-ul-Adha (the Festival of the Sacrifice), and the Days of Tashriq (11th, 12th and 13th of Dhul-Hijjah), (Part No. 9; Page No. 293) except for a Mutamatti` (pilgrim performing `Umrah during the months of Hajj, followed by Hajj in the same year with a break in between) or Qarin (pilgrim combining Hajj and `Umrah without a break in between) who cannot slaughter a Hady (sacrificial animal offered by pilgrims). This is because it was authentically reported from
Ibn `Umar (may Allah be pleased with them both) that they said: It is not permissible to observe Sawm on the Days of Tashriq except for the one who cannot find a Hady.
Al-Bukhari in his Sahih [Authentic Book of Hadith]) In addition, it is forbidden to single out Fridays for observing Sawm because it was authentically reported that the Prophet (peace be upon him) prohibited this except if one fasts a day before or after it.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.