What is the ruling on someone who swore an oath concerning something and then broke it? Is a single day of fasting sufficient as expiation, and if he does the very thing he swore an oath about a second time, is he required to fast again? And is it permissible to fast for expiation while having forgotten its reason?

The expiation for an oath is feeding ten poor persons, or clothing them, or freeing a slave. If one is unable to do these three, then he must fast for three days. Fasting is not sufficient if one is able to perform the other three options. If you break an oath, expiation becomes obligatory upon you. If you repeat the act sworn upon, a second expiation is not required because the oath has been dissolved, unless the wording of the oath implies repetition or you intended the repetition of the breaking of the oath, in which case the expiation is repeated. If you forget the oath or doubt whether you originally swore it, no expiation is due.