Many religions are associated with a particular clothing. Some is mandated in scripture while others are worn as an optional expression of a person's religion. Many religions require modest clothing but do not specify exactly what this entails.
There is often controversy surrounding the extent to which businesses and governments can regulate clothing and how this relates to religious freedom. Often, people go beyond what has been religiously mandated in their choice of clothing while claiming it is a matter of religious freedom. This raises the possibility that any sincerely held view can trump laws or business practices, which is absurd.
If religious clothing is addressed in scripture, it is common for separate rules for men and women. There are separate religious laws regarding clothing to be worn for worship. Some times, religious clothing is enforced by morality police.
The verses commonly cited by Muslims are:
The Quran does not specifically mention any head or hair covering. However, traditionalist Muslims insist that a head covering is required. Islamic women are often socially pressured to conform.  Most Muslims believe that women should have the choice whether to wear a veil. 
- France's burka ban upheld by human rights court.
- Islamic Clothing Requirements
- As a Muslim woman, I see the veil as a rejection of progressive values
There are various styles of head covering and no reliable way to determine which is divinely sanctioned. They range from having the face and neck exposed, the face only, the eyes only to the burka where even they eyes are covered by a mesh. 
Various hadith state that Muhammad told this male followers to grow beards. Most modern Muslims believe it is desirable but not mandatory.  In January 2015, A US Muslim man successfully challenged a prison ban on beards in the Supreme Court.  This raises the question of what other non-mandatory beliefs can trump secular law.
Iran banned various hair styles on the basis they are un-Islamic, stating that "Any shop that cuts hair in the devil worshiping style will be harshly dealt with". 
The Qur'an says post-menstrual women are not to be blamed if they omit the usual clothing. Surah 24:60
Some apologists claim that wearing a head scarf can causes vitamin D deficiency, because it can be naturally generated given sufficient sunlight. There is some scientific evidence that supports this. However, it is easy to take vitamin D supplements to get the required amount.
No clothing of two fabrics. Leviticus 19:19
Transvestism banned Deuteronomy 22:5
Orthodox Jews wear traditional clothing 
Hair and beard guidelines Leviticus 19:27
The guidelines on clothing are generally ignored by Christians. No long hair for men, long hair for women encouraged 1 Cor. 11:14-15 although it must not be plaited. No fancy clothes or golden jewellery for women.
"Whose adorning let it not be that outward adorning of plaiting the hair, and of wearing of gold, or of putting on of apparel;"
"In like manner also, that women adorn themselves in modest apparel, with shamefacedness and sobriety; not with broided hair, or gold, or pearls, or costly array;"
Ironically, it is traditional to wear one's best clothing during Christian worship.
- British Airways Christian employee Nadia Eweida wins case 
While beards were commonly worn by many early Mormons, the church adopted a semi-official anti-beard policy during the 1960s. 
- Kesh (uncut hair)
- Kara (a steel bracelet)
- Kanga (a wooden comb)
- Kaccha - also spelt, Kachh, Kachera (cotton underwear)
- Kirpan (steel sword)
Wearing of a turban is mandatory for all adult males.
Flying Spaghetti Monster
Various US states, including Massachusetts, driving license photos are banned from having hats or head wear except for those worn for religious reasons, because of so called freedom of conscience. Various people have used this exemption to wear a Pastafarian colander in their head for their driving license photo.  Since the religion is generally considered a satirical believe system, this action is probably intended to point out the absurdity of religious exemptions. Having religious beliefs privileged above secular motivations is a violation of church-state separation.
Women should dress modestly
Many religions call on women to dress "modestly". This is usually motivated by the alleged need to help men with their sexual urges but sometimes also to combat materialism.
"I also want the women to dress modestly, with decency and propriety"
- "She avoids clothing designed to draw attention to her body and cause men to lust, for she is wise enough to know that type of attention only cheapens her. "
"And tell the believing women to reduce [some] of their vision and guard their private parts and not expose their adornment except that which [necessarily] appears thereof"
An Iranian cleric, Hojjat ol-eslam Kazem Sediqi, claimed: 
- "Many women who do not dress modestly lead young men astray and spread adultery in society which increases earthquakes [...] What can we do to avoid being buried under the rubble? There is no other solution but to take refuge in religion and to adapt our lives to Islam's moral codes"
These teachings are based on the notion that sexual feelings are automatically bad. This is very repressive of individuals and part of many religions' goal of world renunciation.
Some women claim that wearing a veil makes harassment worse. 
Also, it implicitly shifts the blame of rape on to the victim.
- "the emphasis on modesty that I received growing up is the food and fuel of the rape culture [...] Growing up in a conservative evangelical home, I was taught that the way women dress can cause men to “stumble,” i.e. to think lustful thoughts or fall into sexual sin [...] Cause. Did you see that word? Cause. It wasn’t a typo. I was taught that I could cause a man to fall into sexual sins by dressing immodestly. In other words, if I dressed revealingly his sexual sin would be my responsibility, my fault."
Modest dress does not prevent Iran, Egypt, and many other Islamic countries from having a problem with public harassment of women. It is also enforced at inappropriate times which directly endanger women: such as not allowing evacuation of a building on fire. 
What exactly constitutes "modest" clothing, even among Islamic countries, varies widely. Therefore, this is a culturally subjective practice which could be modified.
Modest dress requirements were satirized by a series of "Boobquake" events in 2010 that encouraged women to immodestly dress in revealing clothes to test if this resulted in a disaster:
- "With the power of our scandalous bodies combined, we should surely produce an earthquake."
The event resulted in no increase in earthquake activity.  The event was jokingly criticised for not having a control group.
Full face coverings in Islam
Full face coverings are considered Islamic in some countries (Saudi Arabia), but un-Islamic in others (some politicians in Egypt). People who argue it is un-Islamic claim that it is not specified anywhere in the Qur'an, and that a non-face covering head scarf is sufficient.
- "How did Islam impose the niqab if Muslims are asked in the Quran to lower their gaze?"
Bans on religious clothing
In 2010, France banned the wearing of burqa and niqab head coverings (as well as balaclavas and hoods) in public places. The Belgian government enacted a similar law in 2011. Several French towns have controversially banned burkini beach clothing.  These cases are interesting because they prioritize social integration over personal and religious freedoms. On the other hand, many Muslims live without feeling the need to wear these types of clothes, so it is a cultural matter, not a matter of freedom of religion. It remains to be seen if these laws promote social integration or rather re-enforce segregation and discrimination in the long term.
- "We created a monster [...] Those who have left to go and fight in Syria say that this law is one of things that encouraged them. They saw it as a law against Islam. It had the effect of sending a message that Islam was not welcome in France [...] But in ten years I have never met a woman who was forced to wear the veil by a man [...] People presented this cliché that Muslim women needed to be saved from men"
- "[the burqa should be banned in] places where it is necessary for our society's coexistence [... it is] not a security issue but an integration issue."
"[...] such general prohibitions on the wearing of full face veils would violate the rights to freedom of expression and religion of those women who choose to wear a full face veil as an expression of their religious, cultural, political or personal identity or beliefs."
- — Amnesty International
Areas that ban full face coverings include: Austria, France, Belgium, the Swiss canton of Tessin, Bulgaria, Netherlands (partially), Lombardy in Italy, Chad. Similar or partial bans are under consideration in Germany, Egypt. Egyptian politicians are ironically considering banning full face veils as they are consider un-Islamic.
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- ↑ Pew, The World’s Muslims: Religion, Politics and Society, 2013
- ↑ http://www.bbc.co.uk/newsround/24118241
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- ↑ Effects of Different Dress Styles on Vitamin D Levels in Healthy Young Jordanian Women
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- ↑ Iranian cleric blames quakes on promiscuous women, BBC, 20 April 2010 
- ↑ 16.0 16.1 
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- ↑ Tinamarie Bernard, Boobquake results: 200,000 women rock the world, not Mother Earth, Examiner, April 27, 2010 
- ↑ 21.0 21.1 21.2 Parliament to draft law banning niqab in government institutions, public places
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