Reference: Fataawa Ramadhaan v2 p707 no.716
Fataawa al-Lajnah ad-Daa.imah lil-Buhooth al-‘Ilmiyyah wal-Iftaa. no.8966
Question: My habit is to fast Mondays, Thursdays and Fridays every week, so is there any harm in that?
Response: If the matter is as you have mentioned, then you have done well so long as you do not single out Fridays alone for fasting, because the Prophet ﷺ said:
«None of you should fast on a Friday unless he [also] fasts the day before or the day after» transmitted by al-Bukhaaree and Muslim.
And with Allaah lies all the success, and may Allaah send prayers and salutations upon our Prophet Muhammad ﷺ and his family and his companions.
