What is the ruling on a charity tied to a specific action, and what is the ruling if it is not fulfilled?

The ruling on a charity conditioned upon a specific action is the same as the ruling on a vow (nadhr). One must refrain from smoking because it is forbidden (haram). This obligation is further confirmed by making a solemn promise to oneself to abandon it, based on Allah’s Almighty words: "O you who have believed, why do you say what you do not do? Great is hatred in the sight of Allah that you say what you do not do" (Quran 61:2-3). If the promise is made verbally, it is binding. However, thoughts to oneself have no ruling. If the promise takes the form of a vow, it is a vow of obstinacy and anger (nadhr lajaj wa ghadab), and upon smoking, one has the choice between giving ten Egyptian pounds in charity or performing an expiation for an oath (kaffarat yamin). If one fails to do either of these, they incur the sin of not fulfilling the vow and the sin of smoking. However, if the promise was not in the form of a vow, the smoker sins by not fulfilling the promise and by engaging in what is forbidden, but no expiation is required of them.