Is the initial commencement of fasting a definitive waiver of the right to revert to the principal expiation acts if ability is later gained?
General Chapter
Al-Mughni
Book of Expiations
Primary text
The commencement of fasting does not invalidate the option to revert to the principal expiation acts (manumission, feeding, or clothing) once the ability to perform them is acquired, because fasting is a valid expiation in itself, even with the ability to perform the principal acts, which contrasts with Tayammum which becomes invalidated by regaining the ability to use water after its completion. Moreover, reverting to water purification is easy, whereas combining two forms of expiation (fasting and then the principal act) for Kaffarah is onerous, and requiring reversion leads to this difficulty.
Supporting text
The argument against this is countered by examining the case of Hajj Tamattu' where, if the pilgrim becomes able to offer the Hady (sacrifice) during the three days of fasting, reversion is not required because the time limit for the Hady (the day of Eid al-Adha) has passed, unlike the situation regarding the Kaffarah where the ability may arise while the original options remain timely.