Is it disliked (Makruh) to fast only on Friday?
General Chapter
Al-Mughni
Book of Fasting
Primary text
It is disliked to fast only on Friday, unless it coincides with a regular fast one observes, such as the practice of fasting every other day, or fasting the first, last, or middle day of the month. Ahmad supports this view, stating the prohibition is against deliberately singling out Friday. The evidence is the statement of the Messenger of Allah, peace be upon him: "None of you should fast on Friday except the day before it or the day after it," as narrated by Abu Hurairah. Jabir also confirmed the prohibition when asked if the Messenger of Allah forbade fasting on Friday. Furthermore, the Prophet commanded a woman who was fasting on Friday, and had not fasted Thursday nor intended to fast Saturday, to break her fast.
Supporting text
Abu Hanifa and Malik hold that singling out Friday for fasting is not disliked because it is a regular day of the week, thus resembling other days.