“Put a piece of meat in various parts of town and see in which place it will get rotten more slowly, that would be the proper place for a hospital.” That was the extraordinarily wise and innovative advice of a famous Iranian physician, who at that time lived in Baghdad, to the people who were in search of the most suitable place for building a hospital.This great physician is no one other than Muhammad Ibn Zakariya Razi, also known as Ar-Razi or Rhazes among European scholars, who for the first time in the history of medicine and chemistry, discovered a chemical substance, which served a great deal to these fields, called “alcohol.”

Rhazes 's Life

He was born in 865 A.D in the city of Rey, located in Iran. Though his father tried so hard to make him follow his occupation which was gold smithery, he finally pursued his interest which was alchemy and chemistry at that time. 

Having spent many years of his life as an alchemist, he eventually found out that the only field worth learning and working in, was medicine. Moreover, as Al-Birooni [1] claimed, he lost his eyesight when he was occupied in alchemy, and finding a cure for this disability became his motive in turning his direction to medicine.

To learn medicine thoroughly, he left his hometown for Baghdad where the most advanced hospitals were located. He studied and practiced medicine at the local hospital. After spending many years in Baghdad and gaining experience, he moved back to his beloved hometown, Rey.

There, he became the head of its local hospital. He is known to have been the first person who introduced the method of teaching medicine in its modern form used today in our hospitals. As compassionate and devoted as he was, he never stopped curing sick people, rich or poor, and teaching medicine to the students of any background.

He died on the 15th of October in 925 A.D where he was born and spent most of his life, in the city of Rey.

Rhazes's Discoveries

According to the Encyclopedia Britannica [2], he was the first physician who differentiated between measles and smallpox. Besides he is considered to be the father of pediatrics and a pioneer in ophthalmology- the study and treatment of eye disorders and diseases.

He also believed in treatment with proper diet rather than prescribing medicines to his patients. The translation of his most important works in medicine such as “Al-Hawi” [3] and “Al-Mansuri” [4] has long been taught in medical universities of European countries such as Germany and France. 

He was a devoted Muslim who was profoundly influenced by the teachings of Islam. His idea about the importance of seeking knowledge with one’s full capacity is in close association with the idea of Prophet Muhammad (PBUH) when he said: “those who peruse knowledge, will be perused by heaven” [4] & [5].

The great Iranian Muslim physician, chemist, and philosopher, Muhammad Ibn Zakariya Razi, with his everlasting contributions in medicine and chemistry, did not remain limited to his time or geographical boundaries. He was the great physician of his time and is considered a respected and influential doctor of our age in all parts of the world.     

Reference:

1. "ar-Razi." Encyclopedia Britannica. Encyclopedia Britannica Online.Jun. 2014  
2. ibid. 
3. Mahmud Najm Abadi, The History of Medicine in Iran and World of Islam.
4. Mottaqi Hindi, Kanz al-Aamal.
5. Muhammad, Mizan al Hekmah, vol. IV, Qum: Dar al-Hadith Institution, 1386. p.398.

Full body ablution (Ghusl) refers to an Islamic ritual in which an adult (Mukallaf) Muslim is recommended to wash his/her full-body with specific rulings. 

In this article, we will explain different types of full-body ablution (Ghusl) and their rulings.

Different types of full body ablution (Ghusl)

Muslim jurists have driven the rules of full-body ablution (Ghusl) based on different verses of the Quran and different narrations and traditions. The main verse of the Quran that is referred to in deriving the rules of full-body ablution (Ghusl) is the following: 

“O you who have faith! Do not approach prayer when you are intoxicated, [not] until you know what you are saying, nor [enter mosques] in the state of ritual impurity until you have washed yourselves, except while passing through. But if you are sick or on a journey, or any of you has come from the toilet, or you have touched women, and you cannot find water, then make your full-body ablution on clean ground and wipe a part of your faces and your hands. Indeed Allah is all-excusing, all-forgiving.” (4:43)

Based on the above verse, Muslim jurists have provided the following rules for full-body ablution (Ghusl):

The obligation of full body ablution (Ghusl)

Different types of full-body ablution (Ghusl) can be categorized as follows: 

1-    The obligatory full body ablution (Ghusl) common between men and women:

a)    The full-body ablution (Ghusl) for ritual impurity (Janabah)
b)    The full-body ablution (Ghusl) for touching a corpse (Mass al-Mayyit)
c)     The full-body ablution (Ghusl) given to a corpse (Mayyit) 
d)     The full-body ablution (Ghusl) that becomes obligatory on the account of a vow (Nazr), oath (Qassam), etc.

2-    The obligatory full body ablution (Ghusl) for women: 

a)     The full-body ablution (Ghusl) for menstruation (Haydh)
b)      The full-body ablution (Ghusl) for lochia (Nifas)
c)      The full-body ablution (Ghusl) for irregular blood discharge (Istihadhah) [1]

3-    Recommended full body ablution (Ghusl)

There are some specific times that Muslims are recommended to perform full-body ablution (Ghusl), for example, the Friday Full-body ablution (Ghusl-e Jum’ah), or the full-body ablution (Ghusl) that are recommended to perform on specific Islamic occasions such as the nights of decree. (Laylatul Qadr). [2]

How to perform full body ablution (Ghusl)?

There are two methods to perform full-body ablution (Ghusl) that will be described in this part. The first thing to do before starting the full-body ablution (Ghusl) is to make an intention for it. However, it is not necessary to perform a separate full-body ablution (Ghusl) for different intentions. 
If there are several recommended (Mustahab) or obligatory full-body ablutions (Ghusl) to be performed and one performs one full-body ablution (Ghusl) with the intention of performing all of them, it is sufficient. However, if one of them is full-body ablution (Ghusl) of ritual impurity (Janabah) and the intention is made to perform it, it suffices for all other full-body ablutions (Ghusl), although caution is to make the intention for all of them. [3]

The methods of full body ablution (Ghusl)

1-    Sequential full-body ablution (Ghusl-e Tartibi)

In sequential full-body ablution (Ghusl), one must – based on obligatory precaution – first, with the intention of full-body ablution (Ghusl), wash the entire head and neck and then the entire body. It is better to first wash the right side of the body, then the left. If one intentionally or due to being negligent in learning the laws of full-body ablution (Ghusl)does not wash the entire head and neck before washing the body, then based on obligatory precaution his full-body ablution (Ghusl)is invalid. Furthermore, based on obligatory precaution, when performing full-body ablution (Ghusl), it is not sufficient to make the intention of full-body ablution (Ghusl) when moving the head, neck, or body while they are already under the flow of water; rather, the part that one wants to perform full-body ablution (Ghusl)on – on the condition that it is already under the flow of water – must be taken out from under the flow of water and then washed with the intention of full-body ablution (Ghusl). [4] 

2-    Immersive full-body ablution (Ghusl-e Irtimasi) can be performed in two ways:

a)    Instantaneous (Daf’i): 

In this type of full-body ablution (Ghusl) water must cover the entire body in one go. However, it is not necessary for the entire body to be out of the water before starting the full-body ablution (Ghusl): rather it will suffice if part of the body is out of the water and the person goes under the water completely with the intention of performing full-body ablution (Ghusl). An example of instantaneous immersive full-body ablution (Ghusl)is when a person, with the int¬ention of performing full-body ablution (Ghusl), dives/jumps into a swimming pool and in doing so completely immerses himself in the water; or, the person may already be partly immersed in the water and he then completely immerses himself with the intention of full-body ablution (Ghusl). [5]

b)    Gradual (Tadriji)

In gradual immersive full-body ablution (Ghusl), one must gradually – but in a way that can be commonly considered to be one unified action – immerse his body in water with the intention of full-body ablution (Ghusl). In this type of full-body ablution (Ghusl), it is necessary for each part of the body to be out of the water before it is washed. An example of gradual immersive full-body ablution (Ghusl) is when a person, with the intention of performing full-body ablution (Ghusl), immerses part of his body in a bath tub of water and then takes that part out of the water; then, he immerses another part of his body and takes it out, and so on until all the parts of his body have been immersed. [6]

Water requirements for full body ablution (Ghusl)

The water that is permissible for full-body ablution (Ghusl) can be Rainwater, Well water, water from spring, sea, or river water, water of melting snow or hail, water of a big tank or pond. Ghusl is not allowed with unclean or impure water or water extracted from fruit and trees. [7] 

References: 

1. Obligatory (wājib) ritual bathing (ghusl) » Introduction
2. Ghusl
3. Rules of Ghusl
4. Obligatory baths (Ghusl) » Sequential ritual bathing (al-ghusl al-tartībī)
5. Obligatory baths (Ghusl) » Immersive ritual bathing (al-ghusl al-irtimāsī)
6. obligatory baths
7. Imam Khomeini, Risalah Tozih al-Masa’el, p. 39-40