to require making up the fast, for Allah has only obligated the month of Ramadan upon the healthy, resident, sane, adult. To oblige fasting some other month in its place is to legislate without Allah’s permission, and such legislation is invalid. There is no difference between Allah’s enjoining the fast of a named month and someone’s asserting—without any revealed text—that fasting another month can stand in its stead, and another who claims that a pilgrimage to somewhere other than Mecca suffices for the pilgrimage to Mecca, or that prayer facing a direction other than the Kaʿbah suffices for prayer toward the Kaʿbah. The same applies to every act of worship. Allah says, “These are the limits set by Allah; so do not overstep them,” and He says, “Whoever transgresses the limits set by Allah has certainly wronged himself.”

He then sets about refuting the opponents who draw an analogy between every deliberate invalidation of the fast and deliberate vomiting, and between that and the man who had intercourse in Ramadan. He also cites statements supporting his view from the Rightly Guided Caliphs—except for ʿUthmān—and from Ibn Masʿūd and Abū Hurayrah; consult his discussion.

I say: as for the man who had intercourse during Ramadan, it is authentically reported that the Prophet ﷺ instructed him to make up the fast as well.