Is one required to offer expiation (Fidya) if they find sandals (Na'l) but cannot wear them while intending to wear leather socks (Khuff)?
Chapter on What the Muhrim Must Avoid and What is Permissible for Him
Al-Mughni
Book of Hajj
Primary text
If a person intending to wear leather socks finds sandals but is unable to wear them, the ruling permits wearing the leather socks, and no expiation is due. This is established because something unusable is treated as non-existent, similar to sandals belonging to another, sandals being too small, or the ruling concerning tayammum when water is unavailable. Inability to wear the sandals stands in the place of non-existence, thus permitting the wearing of the leather socks and consequently nullifying the requirement for expiation.
Supporting text
The explicitly stated position is that expiation is obligatory. This ruling is based on the statement, 'Whoever does not find two sandals, let him wear the two leather socks.' Since the person has found sandals, even if unusable, this ruling applies, necessitating the expiation.