Answered by Shaykh Abdul-Rahim Reasat
Question: Asslamu Alaykum,
Can a non-Muslim uncle be my mahram?
Answer: Wa ‘alaykum as-salam wa rahmatullah wa barakaruh
Thank you for your question.
Who is a Maḥram?
A maḥram is anyone who a Muslim lady cannot marry. This includes her father, son, grandson, brother (biological or through one of them being breastfed the other’s mother), paternal and maternal uncles, nephews, etc. Therefore, your non-Muslim uncle is your maḥram.
There are various rulings of the Shari’a which pertain to maḥram, such as travelling to perform the Ḥajj,and being alone with a maḥram, amongst other things. What the ulema have said is that a Muslim lady may travel with a non-Muslim maḥram, and be alone with him as long as he is not considered morally corrupt according to Islamic standards (Tabyīn al-Ḥaqāʾiq). This is to ensure the safety of the Muslim lady, amongst other things.
You may dress in the presence of your uncle as you would dress in the presence of a Muslim uncle or father unless there is fear of any impropriety. In such a case you would have to cover as you would in front of any other males, showing only your hands and face.
May Allah grant you the best of both worlds.
[Shaykh] Abdul-Rahim Reasat