What is the expiation for failing to fulfill a vow of a religious act?
General Chapter
Al-Mughni
Book of Vows
Primary text
Whoever vows an act of obedience which they are unable to perform, or were able to perform but became incapable, must offer the expiation of an oath (kaffarat yamin). Evidence for this is found in the Hadith where the Prophet (peace be upon him) instructed the sister of 'Uqba ibn 'Amir, who vowed to walk barefoot to the Sacred House, to walk or ride and perform the expiation of an oath. Another narration states she should fast for three days. Furthermore, Aisha narrated that the Prophet (peace be upon him) stated that there is no vow concerning disobedience to Allah, and its expiation is the expiation of an oath, and similarly for a vow one cannot fulfill.
Supporting text
Ibn Abbas stated that whoever vows an unspecified vow, one they cannot fulfill, or one involving disobedience, their expiation is the expiation of an oath, but if they vow one they can fulfill, they must fulfill what they vowed. If the expiation is performed and the vowed act was not fasting, nothing else is due.