Literally Tawheed means "unification" (making something one) or "asserting oneness", and it comes from the Arabic verb (wahhada) which itself means to unite, unify or consolidate.1 However, when the term Tawheed is used in reference to Allaah (i.e. Tawheedullaah2), it means the realizing and maintaining of Allaah's unity in all of man's actions which directly or indirectly relate to Him. It is the belief that Allaah is One, without partner in His dominion and His actions (Ruboobeeyah), One without similitude in His essence and attributes (Asmaa wa Sifaat), and One without rival in His divinity and in worship (Ulooheeyah 'Ebaadah). These three aspects form the basis for the categories into which the science of Tawheed has been traditionally divided. The three overlap and are inseparable to such a degree that whoever omits any one aspect has failed to complete the requirements of Tawheed. The omission of any of the above mentioned aspects of Tawheed is referred to as "Shirk" (lit. sharing); the association of partners with Allaah, which, in Islamic terms, is in fact idolatry.
The three categories of Tawheed are commonly referred to by the following titles:
1. Tawheed ar-Ruboobeeyah (lit. "Maintaining the Unity of Lordship")
2. Tawheed al-Asmaa was-Sifaat (lit. "Maintaining the Unity of Allaah's ****s and Attributes")
3. Tawheed al-'Ebaadah (lit. "Maintaining the Unity of Allaah's Worship")3
The division of Tawheed into its components was not done by the Prophet (saws) nor by his companions, as there was no necessity to analyze such a basic principle of faith in this fashion. However, the foundations of the components are all implied in the verses of the Qur'aan and in the explanatory statements of the Prophet (saws) and his companions, as will became evident to the reader when each category is dealt with in more detail later in this Page.
The necessity for this analytical approach to the principle of Tawheed arose after Islaam spread into Egypt, Byzantium, Persia and India and absorbed the cultures of these regions. It is only natural to expect that when the peoples of these lands entered the fold of Islaam, they would carry with them some of the remnants of their former beliefs. When some of these new converts began to express in writings and discussions, their various philosophical concepts of God, confusion arose in which the pure and simple Unitarian belief of Islaam became threatened. There were also others who had outwardly accepted Islaam but secretly worked to destroy the religion from within, due to their inability to oppose it militarily. This group began to actively propagate distorted ideas about Allaah among the masses in order to tear down the first pillar of Eemaan (faith) and with it Islaam itself.
According to Muslim historians, the first Muslim to express the position of man's free-will and the absence of destiny (Qadar) was an Iraqi convert from Christianity by the **** of Sausan. Sausan later reverted to Christianity but not before infecting his student, Ma'bad ibn Khaalid al-Juhanee from Basrah. Ma'bad spread the teachings of his master until he was caught and executed by the Umayyad Caliph, 'Abdul-Malik ibn Marwaan (685-705), in the year 700 CE.4
The younger Sahaabah (companions of the Prophet (saws)) who were alive during this period, like 'Abdullaah ibn 'Umar (d. 694 CE) and 'Abdullaah in Abee Awfaa (d. 705CE), advised the people not to greet those who denied destiny nor make funeral prayers for those of them who died. That is, they considered them to be disbelievers.5 However, Christian philosophical arguments for free-will continued to find new supporters. Ghailaan ibn Muslim from Damascus studied under Ma'bad and championed the cause of free-will until he was brought before Caliph 'Umar ibn 'Abdul-'Azeez (717-720CE). He recanted his beliefs publicly, however, [and] on the caliph's death, he resumed teaching free-will. The following caliph, Hishaam ibn 'Abdul-Malik (724-743CE), had him arrested, tried and executed.6 Another prominent figure in this controversy was al-Ja'd ibn Dirham, who not only supported the philosophy of free-will, but also attempted to re-interpret the Qur'ânic verses containing de******ions of Allaah's qualities according to neo-platonic philosophy. Al-Ja'd was at one point a tutor for the Umayyad prince, Marwaan ibn Muhammad, who later became the fourteenth caliph (744-750CE). During his lectures in Damascus, he openly denied some of Allaah's attributes, like seeing, hearing etc., until the Umayyad governor expelled him.7 He then fled to Kufah, where he continued to propound his ideas and gather followers until his heretical opinions became widely publicized and the Umayyad governor, Khaalid ibn Abdillaah, had him publicly executed in 736 CE. However, his main disciple, Jahm ibn Safwaan, continued to defend his master's doctrines in philosophical circles in Tirmiz and Balakh, when his heresies became widespread, he was executed by the Umayyad governor, Nasr ibn Sayyaar, in 743CE.8
The early caliphs and their governors were closer to Islamic principles and the consciousness of the masses was higher due to the presence of the Prophet's companions and their students. Hence, the demand for the elimination of open heretics received immediate response from the rulers. In contrast, the later Umayyad caliphs were more corrupt and as such cared little about such religious issues. The masses were also less Islamically conscious and thus were more susceptible to deviant ideas. As greater numbers of people entered Islaam, and the learning of an increasing number of conquered nations was absorbed, the execution of apostates was no longer used to stem the rising tide of heresy. The task of opposing the tide of heresy fell on the shoulders of the Muslim scholars of this period who rose to meet the challenge intellectually. They systematically opposed the various alien philosophies and creeds by categorizing them and countering them with principles deduced from the Qur'aan and the Sunnah. It was out of this defense that the Science of Tawheed emerged with its precisely defined categories and components. This process of specialization occurred simultaneously in all of the other areas of Islamic knowledge as it has done in the various secular sciences of today. Therefore, as the categories of Tawheed are studied separately and in more depth, it must not be forgotten that they are all a part of an organic whole which is itself the foundation of a greater whole, Islaam itself.
Tawheed ar-Ruboobeeyah (Maintaining the Unity of Lordship)

This category is ****d on the fundamental concept that Allaah alone caused all things to exist when there was nothing; He sustains and maintains creation without any need from it or for it; and He is the sole Lord of the universe and its inhabitants without any real challenge to His sovereignty. In Arabic the word used to describe this creator-sustainer quality is Ruboobeeyah which is derived from the root "Rabb" (Lord). According to this category, since God is the only real power in existence, it is He who gave all things the power to move and to change. Nothing happens in creation except what He allows to happen. In recognition of this reality, Prophet Muhammad (saws) used to often repeat the exclamatory phrase "La hawla wa laa quwwata illaa billaah" (There is no movement nor power except by Allaah's will).
The basis for the Ruboobeeyah concept can be found in many Qur'ânic verses. For example, Allaah says:
"Allaah created all things and He Is the agent on which all things depend."9
"And Allaah created you all and whatever you do."10
"It was not you who threw, when you threw, but it was Allaah who threw."11
"And no calamity strikes except by Allaah's permission."12
The Prophet (saws) further elaborated on this concept saying, "Be aware that if the whole of mankind gathered together in order to do something to help you, they would only be able to do something for you which Allaah had already written for you. Likewise, if the whole of mankind gathered together to harm you, they would only be able to do something to harm you which Allaah had already written to happen to you"13