Reference: Fataawa Ramadhaan – Volume 2, Page 592, Fatwa No. 577 al-Muntaqaa min Fataawa ash-Shaykh Saalih ibn Fowzaan – Volume 3, Page 139
Question: A man was struck by a chronic illness, so the doctors advised him not to fast. He was cured of this illness after a period of four years. What should he do now that Allaah has cured him? Should he make up that which has passed?
Response: Anyone who does not fast because of an illness then, after the illness has passed and he is able, it is obligatory for him to make those days up which he was unable to fast. This was mentioned by Allaah (Subhaanahu wa-Ta’aala):
{[Fasting] for a fixed number of days, but if any of you is ill or on a journey, the same number [should be made up] from other days}, [Soorah al-Baqarah, Aayah 184].
For he who had not fasted for four consecutive Ramadhaans and has now been cured, then it is obligatory upon him to make up the days missed [in order]. However, he should distance the days from each other according to his ability to [make up the] fast, until he makes up all that he needs to so that he relieves himself of the responsibility. It is not obligatory for him to make up the days all at once, as that which is mentioned by Allaah (Subhaanahu wa-Ta’aala):
{So keep your duty to Allaah and fear Him as much as you can; listen and obey; and spend in charity, that is better for yourselves. And whosoever is saved from his own covetousness, then they are the successful ones} [Soorah at-Taghaabun, Aayah 16].
This is the case since the time for making up the fasts is plenty.
