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The Relationship between Physical Cleanliness and Moral Purity
Jul 1, 2007

Cleanliness is virtue shared by all people and societies. Physical cleanliness and moral purity are highly encouraged by religions, particularly before the commencement of religious ceremonies, suggesting the existence of a possible psychological relationship between physical cleanliness and moral purity. Recently Dr. Zhong from the University of Toronto and Dr. Liljenquist from Northwestern University published a joint article in Science (September 2006) about the relationship between physical cleanliness and moral purity. They conducted an experiment in which they observed human behavior on this matter. They investigated whether a threat to moral purity activates a need for physical cleansing. Subsequently, they also investigated whether physical purity helps people to deal with the moral threats they face. In a laboratory setting, they asked participants to remember any ethical (good) or unethical (bad) behavior in their life and to explain their emotions and feelings they experienced about this behavior to determine whether the threat to moral purity increased the occurrence of purity-related words. Dr. Zhong and Dr. Liljenquist (2006) documented that people who remembered unethical behaviors about themselves recalled more cleansing words than the ones who remembered ethical ones. They employed three additional experiments by changing their designs and replicated the same results. Their findings indicate that people feel a need for physical cleansing after being involved in unethical behaviors. People feel that they are purified from their sins with physical cleansing.

Before they go to holy places people bathe or shower and then dress in their best clothes. In this way, they are showing their Creator how morally and physically clean they are. Physical cleansing also has benefits for health by removing visible or invisible dirt from the body. As mentioned above, all religions give importance to both physical and moral purity. This article will focus on the Islamic perspective of cleanliness and support it with scientific findings.

The Islamic perspective of cleansing and ablution

In the Islamic belief it is stressed that God’s beloved people are those who are pure and clean. The Prophet Muhammad, peace and blessings be upon him, said: “Cleanliness is half of faith.” This means that physical cleanliness is very important for the purification of the soul and for preparing to worship God. The purity and cleanliness of the body consists of avoiding all external filth and adorning it with cleanliness and good manners.

Traditions of the Prophet about cleanliness

Whenever the Prophet took a bath after intercourse, he started by washing his hands and then performed an ablution that is similar to the one for the prayer. After that he would put his fingers in the water and rub the roots of his hair with them, and then pour three handfuls of water over his head and then pour water all over his body.1

“The taking of a bath on Friday is strongly recommended for every Muslim, and (also) the cleaning of his teeth with miswak, and the using of scents if it is available.”2

Aisha said: “The Prophet passed away in my house and leaning against my chest. One of us would recite a prayer asking God to protect him or her from all evils if he or she became unwell. So I began to ask God to protect him from all evils (by reciting a prayer). . . . Abdur Rahman bin Abu Bakr was passing by with a fresh leaf-stalk of a date-palm and the Prophet looked at it; I thought that the Prophet was in need of it (for cleaning his teeth). So I took it (from Abdur Rahman) and chewed the top of it, shook it and gave it to the Prophet, who cleaned his teeth with it, in the best way he had ever cleaned his teeth, and then he gave it to me. Suddenly his hand dropped down or it fell from his hand (i.e. he passed away). So God allowed my saliva to mix with his saliva on his last day on earth and his first day in the Hereafter.”3

The Prophet said, “Were I not afraid that it would be hard on my followers, I would order them to use the miswak (as obligatory, for cleaning the teeth).”4

Aisha reported: “The Messenger of God, may peace be upon him, said: ‘There are ten acts according to fitra (acts required by human nature): clipping the moustache, letting the beard grow, using miswak (for cleaning the teeth), snuffing water in the nose, cutting the nails, washing between the fingers, plucking the hair under the armpits, shaving pubic hairs and cleaning one’s private parts with water.’ The narrator said: I have forgotten the tenth, but it may have been rinsing the mouth.”5

Abdullah ibn Abbas reported: “I spent (one night) in the house of the Messenger of God (may peace be upon him). He got up, brushed his teeth and performed ablution and said: ‘In the creation of the heavens and the earth, and the alternation of the night and the day, there are indeed signs for people of understanding’ (Al Imran 3:190), reciting to the end of the chapter. He then stood up and prayed two cycles, standing, bowing, and prostrating himself at length in them. Then he finished, went to sleep. He did that three times, six cycles altogether, each time cleaning his teeth, performing ablution, and reciting these verses. Then he observed three cycles of witr. The call to prayer was then heard and he went out for prayer, saying,:” O God! Place light in my heart, light on my tongue, light in my hearing, light in my eyesight, light behind me, and light in front of me, and light above me, and light below me. O God! Grant me light.”6

Ablution and its benefits

There are twenty-six movements to the washing ritual of ablution in Islam, and Muslims perform ablution before they start their daily prayers, going before God with a healthy and clean body. The description of ablution and the importance of physical cleanliness are given in the Qur’an as follows:

O you who believe! When you rise up for the Prayer, wash your faces and your hands up to (and including) the elbows, and lightly rub your heads (with water) and (wash) your feet up to (and including) the ankles. And if you are in the state of major ritual impurity (requiring total ablution), purify yourselves (by taking a bath). But if you are ill, or on a journey, or if any of you has just satisfied a want of nature, or if you have had contact with women, and can find no water, then betake yourselves to pure earth, passing with it lightly over your face and your hands (and forearms up to and including the elbows). God does not will to impose any hardship upon you, but wills to purify you, and to complete His favor upon you, so that you may give thanks. (Maeda 5:6)

According to Prophetic tradition these movements are repeated three times each. Additionally, the inside of the ear, behind the ear and one-third of the head above the forehead are wiped once, according to the traditions of the Prophet. Moreover, the Prophet encouraged making ablution before going bed.

Yoga instructors also teach their students to wash their hands, eyes, legs, mouth, and genitals before going to bed with cold water as well. This act of cleansing prepares the body for a deep sleep [Avadhuta, Vedprajinananda, Yoga Health Secrets].

Ablution stimulates the biological rhythms. In his article entitled “Muslim Rituals and their Effect on the Person’s Health,” Dr. Mogomed Magomedov7 mentions how ablution stimulates the biological rhythms of the body by specifically focusing on the Biological Active Spots (BASes), very much like the idea behind Chinese reflex therapy:

As we know human body is a complex system of electromagnetic fields, meridians, biological rhythms and so on. Man’s internal organs, in their turn, present a bio-energetically sophisticated whole; they all have indissoluble multi-channel bilateral connections with the skin, which hosts special spots, whose functions resemble those of buttons on “control” and “ recharge boards” responsible for particular organs. These spots are called biologically active spots (BASes).

Dr. Magomedov also suggests that his studies are inspired by his solemn belief that five daily prayers each day are bound to have not only an “indisputable spiritual effect,” but are also to have a purely healing effect physically.

Ablution prevents potential health problems. The scholar Mukhtar Salem points out the health benefits of the washing movements in ablution in his book Prayers: A Sport for the Body and Soul. He classifies the benefits of ablution as follows:

1. Ablution helps prevent skin cancer. The author claims that the areas washed during ablution are those parts of the body that are most prone to be exposed to pollution, whether it is pollution from the internal secretions of the body onto the skin surface, such as sweat, or whether it is from external pollution. Ablution removes this “pollution” five times a day, and hence maintains a clean outer layer of skin, which in turn helps the cells underneath to function properly. Also, washing with water helps invigorate the blood vessels, as well as the nerves and glands that are near the surface of the skin, and hence helps them perform their functions efficiently. [Salem, Mukhtar, Prayers: A Sport for the Body and Soul, Cairo, The Arab Modern Center (1990), pg. 52.].

2. Washing the mouth removes food particles, which could cause teeth and gum problems in the mouth. This is also one of the reasons why miswak (or brushing one’s teeth) is recommended.

3. When washing one’s nostrils, one is also performing a preventive health measure as the germs trapped in the nostrils are removed and do not pass onto the respiratory system. According to a study conducted by a team of doctors at Alexandria University, the Prophetic tradition that urges an exaggerated washing of the nostrils by introducing water into the nostril and then blowing it out positively affects the inner coating of the nostrils. Those who carried out the washing in the correct manner had clean, shiny nostrils with no dust clinging to the small hairs inside. However, those who did not perform the ablution had slightly darkened, greasy nostrils and their nostril hairs came away easily.

4. Repeated washing of the face invigorates the facial skin cells and helps prevent early wrinkles, as well as having a cleansing effect on the inside of the eyes, which prevents eye infections. (Salem 1990). Washing the ears also helps get rid of wax accumulation, which may cause ear infections or affect the inner ear, which eventually causes a loss of balance.

5. The Prophetic tradition of encouraging one to wash between the toes while washing the feet is also extremely important, Salem (1990), as this prevents the foot, which in our modern times is trapped most of the day inside shoes, from acquiring athlete’s foot.

Salem (1990) concludes that ablution also has an exercising effect on all the muscles involved in the action, as they are thus being stimulated five times a day or even more according to the frequency of repetition.

Ablution is useful for controlling anger as well. In a hadith8 the Prophet encouraged making ablution when angry in order to cool down and to benefit from the refreshing effect of the water; he stated that anger is from the devil, that it is made out of fire, and can therefore be put out by water.9


Scientific experiments document the relation between physical purity and moral purity. This helps to understand the reasoning behind the encouragement of cleanliness in different belief systems. Ablution is a significant part of the Muslim daily rituals, and it not only has physical benefits but also spiritual benefits, such as stimulating the biological rhythm, preventing health problems, relaxing the body, purifying the soul, and washing away the sins.


  • Avadhuta, Vedprajinananda, 2005, Yoga Health Secrets,
  • Magomed Magomedov, Muslim Rituals & Their Effect On The Person’s Health, their_effct_on_the_person’s_health.htm
  • Salem, Mukhtar, 1990, Prayers: A sport for the soul and body, CAIRO, The Arab Modern Center, p: 52.
  • Zhong, Cen-Bo, and Liljenquist, K, 2006, Washing away Your Sins: Threatened Morality and Physical Cleansing, Science, vol 313, pp: 1451-1452


1. Sahih Bukhari, Volume 1, Book 5, Number 248

2. Narrated by Abu Said, Sahih Bukhari, Volume 2, Book 13, Number 5

3. Narrated by Aisha, Sahih Bukhari, Volume 5, Book 59, Number 732

4. Narrated by Abu Huray ra, Sahih Bukhari, Volume 9, Book 90, Number 346

5. Sahih Muslim, Book 002, Number 0502

6. Sahih Muslim, Book 004, Number 1682

7. Daghestan State Medical Academy, Assistant to the department of the Man’s General Hygiene and Ecology


9 Narrated Atiyyah as-Sa’di.