http://www.usc.edu/dept/MSA/humanrelations/womeninislam/womeninsociety.html
Lowering the Eyes
Islam requires its male and female adherents to avoid illicit sexual relations at all costs. Because the desire to have sexual relationships originates with the look that one person gives another, Islam prohibits a person from casting amorous glances towards another. This is the principle of ghadd al-basar (lowering the eyes). Since it is impossible for people to have their eyes fixed constantly to the ground and inconceivable that a man will never see a woman or a woman will never see a man, Islam absolves from blame the first chance look, but prohibits one from casting a second look or continuing to stare at a face which one finds attractive at first sight.
The following traditions of the Prophet (peace be upon him) offer us guidance in this regard: Jarir says,
"I asked the Prophet what I should do if I happened to cast a look (at a woman) by chance. The Prophet replied, 'Turn your eyes away.' " According to Buraidah, the Prophet told the future fourth khalif, 'Ali, not to cast a second look, for the first look was pardonable but the second was prohibited.
However, there are certain circumstances in which it is permissible for a man to look at another woman. Such circumstances may arise when a woman is obliged to be treated by a male doctor, or has to appear before a judge as a witness, or when a woman is trapped inside a burning house, or is drowning, or when a woman's life or honour is in danger. In such cases, even the prohibited parts of the body of the woman may be seen or touched, and it is not only lawful but obligatory on a man to rescue her from danger, whatever physical contact it may entail. What is required by Islam in such a situation is that as far as possible the man should keep his intentions pure. But if in spite of that his emotions are a little excited naturally, it is not blameworthy for him to have looked at such a woman, since having contact with her body was not intentional but was necessitated by circumstances, and it is not possible for a man to suppress his natural urges completely.
The Shari'ah also allows a man to look at a woman with the object of reaching a decision about whether he should marry her or not. The following traditions explain the matter further: Mughirah ibn Shu'bah says,
"I sent a message to a woman asking for her hand. The Prophet (peace be upon him) said to me, 'Have a look at her for that will enhance love and mutual regard between you.' "
Abu Hurairah says that he was sitting with the Prophet when a man came and said that he intended to marry a woman from among the Ansar (Helpers). The Prophet asked him if he had seen her. He replied in the negative. The Prophet told him to go and have a look at her because the Ansar often had a defect in their eyes. According to Jabir ibn 'Abdullah, the Prophet said that when a man sent a request to a woman for her hand in marriage, he should have a look at her to see if there was anything in her which made him inclined to marry her.
It is thus clear that no man is prohibited from having a look at a woman as such, but that the real idea behind the prohibition is to prevent the evil of illicit intercourse. Therefore what the Prophet has prohibited is only such casting of the eyes as is not essential, as does not serve any social purpose, and as is loaded with sexual motives. This command applies to both Muslim men and Muslim women and is not confined to only one sex.
Maulana Abu'l-A'la Maududi has made a fine psychological distinction, however, between women looking at men and men looking at women. The man, he says,
"...is by nature aggressive. If a thing appeals to him, he is urged from within to acquire it. On the other hand, the woman's nature is one of inhibition and escape. Unless her nature is totally corrupted, she can never become so aggressive, bold, and fearless, as to make the first advances towards the male who has attracted her. In view of this distinction, the Legislator (the Prophet) does not regard a woman's looking at other men to be as harmful as a man's looking at other women. In several traditions it has been reported that the Prophet (peace be upon him) let 'A'isha see a performance given by negroes on the occasion of the 'Id. This shows that there is no absolute prohibition on women looking at other men. What is prohibited is for women to sit in the same gathering together with men and stare at them, or look at them in a manner which may lead to evil results. "
The Prophet (peace be upon him) told Fatimah, daughter of Qais, to pass her 'iddah (waiting term), in the house of Ibn Maktum, the same blind Companion from whom Umm Salamah had been instructed to observe purdah. Qadi Abu Bakr ibn al-'Arabi has related in his Ahkam al- Qur'an that Fatimah, daughter of Qais, wanted to pass her waiting term in the house of Umm Sharik. The Prophet did not approve of this for the reason that the house was visited by many people. Therefore he told her to stay in the house of Ibn Maktum who was blind, where she could stay without observing purdah.
This shows that the real object of the Prophet was to reduce the chances of any mischief occurring. That is why the lady was not allowed to stay in a house where the chances of possible mischief were greater but allowed to stay in a house where they were less. On the other hand, where there was no such need, women were prohibited from sitting in the same place face to face with other men.
The real object of ghadd al-basar (lowering the eyes) is to stop people with evil intentions from casting lewd looks at others. It is common knowledge that a person turns their eyes towards another person innocently in the beginning. If the latter is attractive, the former may go on casting glances and thus drift towards the precipice of sexual attraction and ultimately fornication or adultery. Islam encourages regulated love in order to build up happy family lives since it is healthy families that provide the blocks to construct a healthy society; but it abhors promiscuity which ruins people's family lives and seriously damages people through the ultimate disaster of illicit sexual relationships developing between its adherents. Islam blocks the path that finally leads to active temptation by prohibiting the casting of looks by one person at another except when they do so by chance.
