Whatever we look at or even see, enters our mind and soul, and sticks to them. Imam Ali (AS) said: “The eye is the reporter of heart and the messenger of mind.” [1]. It means that every act of looking profoundly affects our heart and soul. The prophet (PBUH&HP) said: “Avoid unnecessary excess looks as they grow lust in your hearts and make you heedless.” [2].

In another saying from Imam Ali (AS), we read that: “The eyes are the snares of Satan” [3]. That is why Islam has special guidelines and rules about at what or whom, one is allowed or not to look. And, this is more pressing in case of Muslims living in a non-Muslim society, where they are constantly exposed to both men and women freely and improperly dressed in the streets, TV, magazines, web pages, etc. Islam has regulated looking at the opposite gender according to the two categories: Mahrams and non-Mahrams [4].

Men Looking at Mahram Women 

A man is permitted to look at the body of a woman who is his Mahram, except her private parts (Awrah). And he must not look at her body from the navel down to the knee. This means that a woman should dress decently even in the presence of her Mahrams. One’s wife is an exception to this rule; married couples are allowed to look at the entire body of each other.

Men Looking at non-Mahram Women

It is forbidden for a man to look at the body of any non-Mahram woman but he can look at her hands and face as long as they do not have any decoration. If the woman is Muslim, then he is not allowed to look at her hair. But if she is not Muslim, looking at her hair is not forbidden as long as it is not for pleasure.

Generally, there is no sin on a man for the first involuntary look at any non-Mahram woman, but the second look should be avoided [5]. In any case, men should remember that: “Tell the faithful men to cast down their looks and to guard their private parts. That is more decent for them.” (24:30).

This rule also extends to adolescent boys and even younger ones, who understand women’s physical attributes and might be attracted to them. They should be taught to lower their gaze, too. Since children’s minds and souls are clear lands ready to be cultivated with several types of thoughts and ideas mostly captured by eyes, we need to teach them which seeds they should plant in their lands to attain Allah’s eternal satisfaction.

Men Looking at Other Men and Women Looking at Other Women

A man is not allowed to look at another man’s private parts, nor a woman at those of another woman; whether Muslim or not. Besides, looking at any parts of the body of another man, even the face and arms, will be forbidden for a man if done with the intention of having pleasure. The same ruling applies to a woman towards another woman. This also means that one should always cover his/her private parts in the presence of others, even of the same gender.

Women Looking at Mahram Men

A woman is allowed to look at the body of a man who is her Mahram, except his private parts, if it is not for having pleasure. One’s husband is an exception to this rule as mentioned earlier. 

Women Looking at non-Mahram Men

A woman is not permitted to look at the body of a non-Mahram man, except for the face, hands, and that amount which men usually [i] do not cover and if it is not for pleasure.

Looking at a Small Child's Private Parts

One is permitted to look at the entire body of a child until he/she reaches the age when the child’s consciousness of sex has developed, or when evidence of sexual urge is noticed on him/her; even if it is before reaching puberty. However, it is better to accustom the child to always dress properly.

As a general rule, it is forbidden (Haram) to look at anyone (even at one’s own body) or anything (including people’s photos and films, statues, etc.) with the intention of having pleasure (with the exception of one’s spouse), even if one is looking at a Mahram.

In cases of “necessity” such as in administering first aid, medical treatment [ii] or during a trial testimony where the judge requests the witness to look at a non-Mahram to identify him/her [6], all the rules of the prohibition of looking become void. As an instance, if a doctor is compelled to look at a part of the body of a non-Mahram woman, he must only look at that part necessary for the treatment, but not more than that. Also, if possible, the examination or testing must be performed over the clothing. Other exceptions are looking at one’s spouse as explained above.

Notes:

[i] This, although following a definite limit indicated in Islamic ruling that should be respected, is based on the normal condition of each society to some extent.

[ii] In the case that a doctor of the same skill and with the same gender is not available.

References:

1. M. B. Majlesi, “Bihar al-Anwar”, vol. 104, p. 41, T. 52.
2. M. B. Majlesi, “Bihar al-Anwar”, vol. 72, p. 199.
3. M. B. Majlesi, “Bihar al-Anwar”, vol. 77, p. 294.
4. www.al-islam.org
5. Ibn Babawayh, “Man la yahduruhu al-Faqih”, vol.3, p.474, T. 4658.
6. looking to others

Every day we meet several people at work, in the shops, at the university, in the neighborhood, or at parties and gatherings with whom we communicate and interact. Talking, telling jokes, shaking hands, touching or kissing usually happen in these interactions; but, is a Muslim allowed to do all these with whoever he/she wants? Or is he/she permitted to be exposed to such acts?  These and many similar questions are answered in Islam.

To clarify and form the relations among people, Islam has presented the concept of Maharim and the two categories “Mahram” and “non-Mahram” which sometimes serve as conditions, requirements, or the basis of several Islamic laws. Regarding the Islamic rules on marriage, these categories define who a person can and cannot marry. Likewise, when dealing with the Islamic dress code, i.e., explaining whom one must cover specific parts of a body in front of, the concept of Maharim is required.

Who is Mahram?

One’s Mahram is anyone whom it is permanently forbidden to marry because of blood ties, marriage ties or breastfeeding. However, a woman does not need to cover her hair and put on Hijab when she is in their presence.  A woman's male Mahrams fall into three categories plus her spouse [1]. Mahrams for a man are derived similarly. The Maharim for both, extracted from the verses of the Holy Quran (4:22-23) and (24:31), are listed below [1], and all other people and relatives are considered as non-Maharams.

Categories of Maharim

Permanent or blood Mahrams, with whom one is Mahram through blood ties:
parents, grandparents, and further ancestors;
siblings;
children, grandchildren, and further descendants;
siblings of parents, grandparents, and further ancestors (cousins and their children are not Mahram);
children and further descendants of siblings;
In-law Mahrams, with whom one becomes Mahram through marriage ties:
father-in-law, mother-in-law;
son-in-law, daughter-in-law;
stepfather (mother's husband) if their marriage is consummated, stepmother (father's wife) even if their marriage is not consummated;
stepson (husband's son) even if their marriage is not consummated, stepdaughter (wife's daughter) if their marriage is consummated[i];
Rada or "milk-suckling Mahrams," with whom one becomes Mahram because of being breastfed by her. When a woman breastfeeds an infant that is not her child for a certain amount of time under certain conditions, she becomes the child's rada mother and everything concerning blood Mahrams apply here, such as rada father/mother, rada sister/brother, rada aunt/uncle and so on. In English, these can be referred to as milk-brother, milk-mother, etc. [ii].

Maharim and Marriage

It is forbidden (Haram) to marry Mahrams, but one can marry non-Mahrams who have reached puberty. As explained above, Married couples are Mahram to each other. But unlike other Mahrams, the limitations and rulings on looking and touching do not apply to them; i.e., married couples are the only ones allowed to touch and look at the whole body of one another; even the private parts. 

Maharim and Social Interactions

Regarding social interactions, there are some rules according to the concept of Maharim:

Women and men are both required to keep their gazes downcast and should not stare at the other person when facing non-Mahrams or talk to them. Even Mahrams are not allowed to see certain parts of the body of each other (this will be discussed more under a separate topic “the Islamic rules on looking“);
When talking to non-Mahrams, the tone of voice should be serious, and the dialogues should be direct and as much as necessary. One should also avoid telling jokes and laughing loudly [iii];
Any physical contact (i.e., shaking hands, hugging touching) with non-Mahrams is forbidden (haram), except for curing patients. In this case, if a doctor of the same gender as the patient exists and can cure, then it is forbidden to refer to a non-Mahram doctor.
When being sole in a closed room (where no one else can enter, i.e., locked place), it is forbidden for a non-Mahram man to remain alone in the company of a non-Mahram woman. The Prophet of Islam (PBUH&HP) said: “No man is alone with a woman except that Satan is the third one present ” [2];
It is required (Wajib) to cover specific parts of a body in the presence of a non-Mahram according to the Islamic dress code. For men, this includes from navel to knee. For women, the clothing should cover their hair and body, but covering the face and the hands, from the wrist to the fingers, is not mandated [3].

Notes:
[i] sister-in-law and brother-in-law are not Mahram.

[ii] Refer to your source of emulation (Marja’ Taqlid) for more details and the rulings.

[iii] See the article on modesty.

References: 

1. Mahram and non Mahram
2. S. H. al-Amili, “Wasail al-Shia”, vol. 20, p. 131.
3. A. Aroussi Howayzi, “Tafsir Noor al-Thaqalayn”, vol. 3/589, T. 105.