The books of hadith deal with this question when they discuss the issue of covering he body in prayer, or when explaining the verse in Surah An-Nur (24:31), or in the section dealing with dress.
The books consulted are: Ibn Hajar's Fath al-Bari, al-Shawkani's Nayl al-Awtar, al-Nawawi's Sharh Sahih Muslim, a commentary on Muslim and al-Banna's al_Fath al-Rabbani, a commentary on Musnad of Ahmad ibn Hambal.
Al-Shawkani also touched this subject when he quoted a hadith reported by al-Bukhari on three occasions--in his discussion of the time for fajr prayer. He mentioned the hadith of Aisyah that Muslim women used to offer their fajr prayer with the Prophet, covering their heads, then they would disperse, unrecognized because of the darkness. Al-Bukhari added: "They did not even recognize one another." Then al-Shawkani said:
Al-Baqi said: "This shows that the women used to unveil their faces, it would have been difficult to recognize them whether it was dark in the early morning or it was light. i.e. the fact that it was dark would have made no difference."
It is in the sections of his book dealing with the covering of the aurah that al-Shawkani elaborated on this point; under the title "The whole body of the omen is aurah except for the face and the hands." Here, he quoted the hadith of Aisyah r.a in which the Messenger of Allah said: "Allah will not accept the prayer of a woman who has reached the age of puberty unless she covers her head." He then explained the word khimar as meaning the head cover, and said: "This hadith is one of the proofs that the woman must cover her head during her prayer."
He went on to define the aurah of a free woman. According to ne view, it is all of her body exept the face and the hands. This is the view of Abu Hanifah; al-Qasim on of his two views; al-Shafie in one of his views; Abu Hanifah in one of his two statements and Malik (where scholars are said to have more than one view, this reflects the variance in the practice of the Prophet himself as reported in the hadith). The other view held is that the awrah includes the two view of al-Qasim--in one view and Abu Hanifah--in another of his statements. The third view is that the aurah comprises the whole of the woman's body, except the face. This is the view of Ibn Hanbal and Dawud, the literalist. The fourth view is that the entire body with no exception is aurah.The important point in this discussion, which will answer the objections of those who differentiate between prayer and daily life, is the fact that al-Shawkani refers the whole discussion and the difference of opinions to the discussion about the interpretation of the verse which tells women not to
"display their beauty and ornaments except what (must ordinarily) appear thereof" (Surah an-Nur 24:31)
which is basically the statement of general application in daily life and social interaction, not the specific time of prayer. He said: "The difference here is the result of the difference there."In Fath al-Bari, when discussing the fajr prayer in the book "The times of prayer", Ibn Hajar quoted the ame hadith narrated by Aisyah r.a., which is referred to above. Noting that he was writing in the 9th century of hijrah and al-Shawkani in the 13th, it follows that al-Shawkani must have been quoting Ibn Hajar and the statement of al-Baqi. But a valid point to be noted here is the implication of the hadith, as stated by Ibn Hajar. The hadith allows women to attend prayer in the mosque at dawn and dusk so it is to be understood that it is permitted for them to do so during the day--for night is the time when there is suspicion of doubtful things, much more so than during the day. But this is only the case when there is no fear of seduction for them or from them.
Al-Banna, in al-Fath al-Rabbani, a commentary on Ibn Hanbal's collection of hadith, discusses the issue under the same title, "Covering the aurah". In the section on "What is reported concerning the woman's bdy being aurah except for the face and the hands", Ibn Hanbal quoted Aisyah's staying at the house of Safiyyah. There she saw some young girls who were offering their prayers without covering their heads. Aisyah said:
"They should not pray without a cover on their heads. One day the Messenger of Allah entered the house. There was a young girl in my custody. He handed me a piece of cloth saying, 'Cut it into two pieces, one for your maid and other for Ummu Salamah's maid for it appears that they both have reached the age of womanhood'."
Al-Banna went through the discussion as Ibn Hajar and al-Shawkani, quoting almost the same arguments. Then he added: "Imam al-Nawawi, in his noted on Muslim's collection of ahadith, mentioned a good number of rules which it is good to mention here. These are the general rules dealing with aurah."
This however, is not the place for such a discussion. But it is in another area which is related to the question of awrah that we find al-Nawawi making it clear that the face and the hands are not part of the aurah, whether in prayer or outside of it. It is in the book of marriagem in the section on the recommendation for the person wishing to marry a woman, that he should look at the face and the hands before proposing to her:
Abu Hurairah reported that a man came to the Prophet to tell him that he proposed to an Ansari woman. The prophet asked him, "Have you seen her? For the women in Madinah have some defects in their eyes."
Al-Nawawi said: "This hadith recommends looking at the face of the women when a person wishes to marry her. This is our (Shafi'i) view, and the view of Malik, Abu Hanifah, Ibn Hanbal and the view of the overwhelming majority of the scholars."Al-Qadi reported that some people said it was not desirable to look at a woman whom one wishes to marry. This view is in conflict with the clear words of the hadith, the consensus of the Muslim nation of the permissibility to look at the face of the woman in buying selling, bearing testimony and the like. In those cases, the permission is limited to the face and the hands, because they are not aurah. Al-Shawkani deals with the question of privacy and aurah in the book of marriage. In the section "The prohibition of sitting in privacy with a strange woman unless there is a close relative present with her.", he quotes six hadith to the effect that there should be no privacy between a male and a female unless there is a mahram present. A man i not allowed to look at the private parts (front and back) of another man, and a woman is not allowed to look at the private parts (front and back) of another woman; a man should not touch the naked body of another man, i.e. not lie next to one another semi naked; a man may look 'accidentally' at a woman but it is forbidden to follow the accidental look with an intentional one; and rules concerning the in-laws. All these traditions were quoted. After a lengthy discussion, he qoted al-Amiri, the Shafi'i, as saying regarding the events of 5th hijri: In this year the Verses of the Veil (Surah al-Ahzab, 33-53) was revealed. In it there are great benefits and courteous manners. After this revelation, it became forbidden to look at strange women with or without passion or desire. But the accidental glance is forgiven. Imam Yahya, a Zaydi Shi'I, and those who followed him say: "It is allowed to look at a strange woman, with or without passion."
Consequently, the following important discussion developed: among the proofs advanced by those who forbid looking generally are:
Say to the believing men that they should lower their gaze.. (Surah An-Nur: 30) and the Verses of the Veil, Surah al-Ahzab 33-53.
The answer to this line of argument is that the Verse of the Veil is addressed specifically to the wives of the Prophet, and it is well known that we are bound by the general rule, not the particular case.
Other evidence regarding the prohibition of looking at a strange woman is the incident concerning the beautiful young woman of Khasam, who was asking the Prophet some questions--during the Farewell Pilgrimage. His cousin al-Fadl Ibn `Abbas was riding behind the Prophet and kept looking at her and the Prophet kept turning his face away. The reason for this is the Prophet feared seduction on the part of the two young people. Ibn al-Qattan inferred from the allowability of looking when there is no fear of seduction, because the Prophet did not command her to cover her face.
Al-Shawkani said:
This sound hadith may be taken as a prof that the Verse of the Veil (33:53) is a special rule for the wives of the Prophet, for the Verse of the Veil was revealed earlier, in the fifth year, whilst this incident took place in the final year of the Prophet's life.
But the most important comment given by al-Shawkani here in his saying:
To sum up, it must be said that the woman is allowed to uncover the places of the adornment as necessary, when performing her affair, when transacting, when testifying--all these are exceptions from the place of adornment which she is forbidden to expose. This view, assuming that there is no explanation handed down allowing such exception. But in the following section texts ill be quoted which will show that the face and the two hands are exempted.
What is meant here is that the words of verse 24:31 themselves give the impression even if they were not explained with an explanation handed down to that effect, i.e. even if there is no tafsir to that effect handed don from the Prophet the text itself is self-explanatory. But when we consider the saying of Ibn `Abbas, which is accepted by majority of Muslim Scholars, the matter becomes clearer, that the face and the hands are not aurah.
Source: Hijaab or Niqaab - An Islamic Critiques of the face-veil
by Syed Mutawalli Ad-Darsh