After we said that hearing the voice of a non-mahram woman...
After we said that hearing the voice of a non-mahram woman is not a problem and that it is permissible for a man to look at the face of a non-mahram woman as long as it is not a lustful look, then she may be a teacher of male students. That is, the limits are this very face and hands. The truth is that the real question is whether or not women have to be limited to the home or not. This is not a small issue.
If we deduce that the view of Islam is that the face and hands of women must be covered along with the rest of her body, which is obligatory to be covered and if we say that a woman must be covered from head to toe, this means that the activities of a woman must be limited to her home because it is not possible for her to be active outside of her home. But if we say, no, it is not obligatory for women to cover their face and hands, we have not limited her activities with this.
For instance, women who believe that they are obliged to cover themselves completely cannot ever leave their homes to go shopping for vegetables. She has to send a male servant or her husband to do this. Thus there is a great difference in whether or not it is obligatory for a woman to cover her face and hands. The area of her activities could become extremely limited. We have deduced from the verses of the Holy Quran and the traditions.
The only thing we found a lack of was religious edicts and this was not in relation to it being compulsory to cover the face and hand. Most edicts agree that it is not. The area in which there is a lack of religious edicts sensed is in the area of whether or not it is permissible for a man to look at the face of an un-related women as long as his look is not of lust.
The majority says it is not permissible but there are people like the great Alim Shaykh Ansari who say it is permissible and in the verse itself and in the traditions, it was very clearly permissible. Thus if we are asked, "What is the difference between the face and the hair? Does not the criterion which exists for the hair exist for the face? For the eyes and eyebrows?
These criteria even carry more weight here." The answers are that it is an allowable expedience, not an allowable non-expedience, that a criterion which exists for one does not exist for another. Also, in the exception which exists in relation to individuals, there are two exceptions which we will discuss later. Covering from one's father, one's children, the sons of one's husband, brothers, father-in-law, etc.