Making up missed obligatory fasts for my deceased father

Answer

Wa’alaykum as Salam wa rahmatullahi wa batakatuhu,

According to Hanafies, Malikies, Shafies and the vast majority of scholars, the narration which you quoted is Mansukh (abrogated). Amongst other reasons, the narrator of the Hadith, Aaisha (may Allah be pleased with her) herself gave Fatwaa (verdict) that no one is allowed to keep fast on behalf of a deceased. That proves that she must have heard another statement from the Prophet (sallallahu alayhi wa sallam) which cancels the ruling in the narration which you quoted. Likewise, other Sahaba too issued similar verdicts; that it is not permissible to fast on behalf of one who passed away.

The method of making up for the fasts on behalf of your dad is as follows:

If he bequeathed that the Fidya (penalty) for the missed fasts be given from his estate, then the heirs are obligated to discharge the Fidya on his behalf from one third of what remains after burial expenses and paying off debts.

However, if your father did not make such a bequest, then the heirs are not obligated to give any amount of money as Fidya on his behalf.

Nevertheless, in such a case it will be a noble action on your path to discharge the Fidya on his behalf from your own wealth.

The Fidya for each fast which he missed is the same as Sadaqah al-Fitr – half a Saa’ (2.32 kg) of wheat (or its monetary equivalent in your country).

References

قال النسائي أنبأ محمد بن عبد الأعلى ثنا يزيد بن زريع ثناحجاج الأحول ثنا أيوب بن موسى عن عطاء بن أبي رباح عن ابن عباس ، قال : لا يصلي أحد عن أحد ، ولا يصوم أحد عن أحد ، ولكن يطعم عنه مكان كل يوم مدا من حنطة” (رواه النسائي في ” سننه الكبرى – 175 / 2)

 حدث عبد اارزاق عن عبد الله بن عمر عن نافع عن ابن عمر ، أنه قال : “لا يصلين أحد عن أحد ولا يصومن أحد عن أحد” (أخرجه عبد الرزاق في مصنفه – 61 / 9)

  فيخرج عنه وليه من ثلث ما ترك لصوم كل يوم و لصلوة كل وقت، حتي الوتر (نور الايضاح، ص 132)

يعطي لكل صلوة نصف صاع من بر كالفطرة ز كذا حكم الوتر و الصوم ( الدر المختار –  101 / 1)