✅ Answer: The Infallible Imams (peace be upon them) provide the following guidance:

1 عَنْ مُحَمَّدِ بْنِ مُسْلِمٍ عَنْ أَبِي جَعْفَرٍ قَالَ: قُلْتُ لَهُ رَجُلٌ مَرِضَ فَتَرَكَ النَّافِلَةَ فَقَالَ يَا مُحَمَّدُ لَيْسَتْ بِفَرِيضَةٍ إِنْ قَضَاهَا فَهُوَ خَيْرٌ يَفْعَلُهُ وَ إِنْ لَمْ يَفْعَلْ فَلَا شَيْ ءَ عَلَيْهِ.

📚 Al-Faqih, Vol.1, p.499

Muhammad ibn Muslim said: I asked Imam al-Baqir (peace be upon him): A man fell ill and missed his nafl prayers. What is his duty? The Imam replied: O Muhammad! These are not obligatory. If he makes them up, it is a good deed, but if he does not, nothing is required of him.

2 عَلِيُّ بْنُ إِبْرَاهِيمَ عَنْ أَبِيهِ عَنِ ابْنِ أَبِي عُمَيْرٍ عَنْ مُرَازِمٍ قَالَ سَأَلَ إِسْمَاعِيلُ بْنُ جَابِرٍ أَبَا عَبْدِ اللَّه فَقَالَ أَصْلَحَكَ اللَّهُ إِنَّ عَلَيَّ نَوَافِلَ كَثِيرَةً فَكَيْفَ أَصْنَعُ فَقَالَ اقْضِهَا فَقَالَ لَهُ إِنَّهَا أَكْثَرُ مِنْ ذَلِكَ قَالَ اقْضِهَا قَالَ لَا أُحْصِيهَا قَالَ تَوَخَّ قَالَ مُرَازِمٌ وَ كُنْتُ مَرِضْتُ أَرْبَعَةَ أَشْهُرٍ لَمْ أَتَنَفَّلْ فِيهَا فَقُلْتُ أَصْلَحَكَ اللَّهُ أَوْ جُعِلْتُ فِدَاكَ إِنِّي مَرِضْتُ أَرْبَعَةَ أَشْهُرٍ لَمْ أُصَلِّ فِيهَا نَافِلَةً فَقَالَ لَيْسَ عَلَيْكَ قَضَاءٌ إِنَّ الْمَرِيضَ لَيْسَ كَالصَّحِيحِ كُلَّمَا غَلَبَ اللَّهُ عَلَيْهِ فَاللَّهُ أَوْلَى بِالْعُذْرِ فِيهِ

📚 Al-Kafi, Vol.3, p.451

Marazm said: Isma'il ibn Jabir asked Imam al-Sadiq (peace be upon him): May God improve your affairs. I have many nafl prayers. What should I do? The Imam replied: Make them up!

He said to the Imam: There are even more nafl prayers than I can make up!

The Imam said: Make them up!

He said: I cannot count them all!

The Imam said: Estimate them!

Marazm said: I was ill for four months and did not perform the nafl prayers. I said to the Imam: May God improve your affairs! I was ill for four months and did not perform the nafl prayers.

The Imam said: It is not obligatory for you to make them up. A sick person is not like a healthy person. Whatever God prevails over a servant with, God is more worthy of accepting the excuse.

✅ Although according to Shia narrations, daily nafl prayers are not obligatory, there is strong encouragement to make up missed nafl prayers. However, in the case of missing nafl prayers due to illness, while making them up is described as a good deed in the first narration, both narrations permit leaving them without making them up.

اللَّهُمَّ فَصَلِّ عَلَی مُحَمَّدٍ وَ آلِ مُحَمَّدٍ وَ عَجِّلْ لِوَلِیِّکَ الْفَرَجَ وَ الْعَافِیَةَ وَ النَّصْرَ