Thirty-first: It (1) is disliked to single out Friday for fasting. This is Ahmad’s explicit position. Al-Athram said: Abū Abd Allāh was asked, “What about fasting on Friday?” He cited the hadith prohibiting (2) singling it out, then said, “Unless it falls within a fasting routine one already follows; but singling it out—no.” I asked, “Suppose a man fasts on alternate days, so that Thursday is a day when he does not fast, Friday a day when he fasts, and Saturday a day when he does not fast. Friday would then be a day fasted on its own?” He replied, “In this case, he has not deliberately (3) singled it out for fasting. What is disliked is deliberately singling out Friday (4).”
Mālik and Abū Hanīfah permitted fasting on Friday as on any other day (5). Mālik said (6): “I have not heard any scholar or jurist, or anyone whose example is followed, prohibit fasting on Friday. Fasting on it is good. I have seen some scholars fast on it, and I believe they would deliberately choose it.”
Ibn Abd al-Barr said (7): The reports from the Prophet, peace and blessings be upon him, differ concerning fasting on Friday. Ibn Masʿūd related that the Prophet, peace and blessings be upon him, used to fast three days of every month, and said, “I rarely saw him refrain from fasting on Friday” (8). This is an authentic hadith.