
Shaykh Isam Rajab said the following:
Regarding the face covering for women some scholars said that it's permissible to cover the face if there are men based on the incident of Aisha Radiallahu Anha where she said that she used to cover her face once men passed by.
I don't believe it's permissible for women to cover their faces as the Messenger Sallallahualaihi wasallam said: "The woman is not to put her niqab on during Ihram".
So here's a hadith from the Messenger Sallallahualaihi wasallam Vs. an action of Aisha Radiallahu Anha and we're commanded to follow the Messenger Sallallahualaihi wasallam.
Also, the famous story of Al Fadl Ibn Abbas Radiallahu Anhuma and the woman who asked the Messenger Sallallahualaihi wasallam. The Prophet Sallallahualaihi Wasallam would've told her cover your face instead of turing the face of Al Fadl several times!
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