When must a vow to quit smoking, avoid looking at forbidden things, and memorize five parts of the Quran—made for the improvement of the father's health—be fulfilled? Is it necessary to hasten its fulfillment? Is it a valid vow, and what expiation is required for not fulfilling it?

A vow to quit smoking and to avoid looking at forbidden things is an obligatory vow that is not binding and does not require expiation. As for a vow to memorize parts of the Quran, it is a binding vow of obedience that must be fulfilled upon the occurrence of the condition upon which it is suspended. It is permissible to delay it as long as no specific time has been appointed for it, and expiation is not sufficient for it as long as one is able to fulfill it.