بسم اللہ الرحمٰن الرحیم

:الجواب وباللہ التوفیق

A woman's financial or personal assistance to a sick non-mahram male relative, treating him nicely and providing comforting company to him is a good thing. But in providing so, proper hijab and purdah must be observed. It is also important to refrain from being alone and in solitude with him. 

During your visits to him one of your “Mahrams” must be with you. More importantly, during his personal and physical needs. In situations where Hijab and Purdah cannot be managed, then it is not allowed for you to undertake that responsibility. More specifically, if that non-mahram needs cleaning for “istinjaa”, etc., then this service of his is not permissible for you carry out. For that, either a male relative should be asked to take up responsibility of this service, or a male person should be hired with wages. If no one can be found, then the requirement of “istinjaa” shall become null and void. 

For a woman to serve a non-mahram in those specific matters is not permissible at all.

فَلَوْ مَشْلُولَةً وَلَمْ يَجِدْ مَاءً جَارِيًا وَلَا صَابًّا تَرَكَ الْمَاءَ، وَلَوْ شُلَّتَا سَقَطَ أَصْلًا كَمَرِيضٍ وَمَرِيضَةٍ لَمْ يَجِدَا مَنْ يَحِلُّ جِمَاعہ

)قَوْلُهُ: سَقَطَ أَصْلًا) أَيْ: بِالْمَاءِ وَالْحَجَرِ. (قَوْلُهُ: كَمَرِيضٍ إلَخْ) فِي التَّتَارْخَانِيَّة: الرَّجُلُ الْمَرِيضُ إذَا لَمْ تَكُنْ لَهُ امْرَأَةٌ وَلَا أَمَةٌ وَلَهُ ابْنٌ أَوْ أَخٌ وَهُوَ لَا يَقْدِرُ عَلَى الْوُضُوءِ قَالَ يُوَضِّئُهُ ابْنُهُ أَوْ أَخُوهُ غَيْرَ الِاسْتِنْجَاءِ؛ فَإِنَّهُ لَا يَمَسُّ فَرْجَهُ وَيَسْقُطُ عَنْهُ وَالْمَرْأَ الْمَرِيضَةُ إذَا لَمْ يَكُنْ لَهَا زَوْجٌ وَهِيَ لَا تَقْدِرُ عَلَى الْوُضُوءِ وَلَهَا بِنْتٌ أَوْ أُخْتٌ تُوَضِّئُهَا وَيَسْقُطُ عَنْهَا الِاسْتِنْجَاءُ.(رد المحتار: ۱/۳۴۰)

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