As-Salaam-Mu-Alaykum.
1. I understand that purdah (i.e. covering the face) for a women is Waajib, but I seem to have to argue this with others the as to reason why it is Waajib, as I don’t know the whether it is stated in the Quraan / Hadith, can Mufti please tell me how I should explain why purdah is Waajib? And if it is true that the wives of the Prophet (SAW) never covered their faces?