The science of Source Methodology in Islamic Jurisprudence Usul al Fiqh has been defined as the aggregate, considered per se, of legal proofs and evidence that, when studied properly, will lead either to certain knowledge of a Shari'ah ruling or to at least a reasonable assumption concerning the same; the manner by which such proofs are adduced, and the status of the adducer.1

Subject Matter:

As its subject matter, this science deals with the proofs in the Shari'ah source-texts, viewing them from the perspective of how, by means of Ijtihad , legal judgements are derived from their particulars; though after, in cases where texts may appear mutually contradictory, preference has been established.2


The science of Usul al Fiqh engenders the ability to have knowledge of Shari'ah rulings through study, on the part of those qualified to perform Ijtihad and who meet all its requirements, of the legal proofs revealed in the sources by the Lawgiver.

The benefit to be had from this science to those not qualified to perform Ijtihad is that, through their study of the classical schools of legal thought madhahib of the mujtahidun (those who practise Ijtihad ) and the reasoning behind their rulings, the student of Source Methodology in Islamic Jurisprudence is enabled to understand the various schools of thought, to analyze them, to choose from among their interpretations and assign preference, and to adduce legal arguments on the basis of the principles formulated by the classical mujtahidun.


The science of Usul al Fiqh is in fact an independent and autonomous field. It is, however, based on certain fundamental predications muqaddamat, knowledge of which the Islamic legal scholar cannot do without. These predications have been derived from several other disciplines:

  1. Some are derived from the science of Aristotelian logic which the philosopher-theologian writers mutakallimun had become accustomed to discussing in the introductions to their works. These academic discussions dealt, for example, with the ways in which words convey meanings, the division of subjects into present and predicable, the need for, and varieties of, discourse depending on conceptual principles taken from interpretations and definitions, the validity of conclusions based on inductive reasoning, and discussions about evidence and how it may be used to prove the claims of the one who is adducing it, or to refute contradictions, and so on.
  2. Some are derived from Ilm al Kalam Scholastic Theology, and include discussions of such questions as the nature of the Sovereign Hakim, in the sense of whether it is the Shari'ah itself or reason which decides what is right and what is wrong; or such as whether one can have knowledge of right and wrong before revelation; or such as whether rendering thanks to the Bounteous Creator is a duty derived from the Shari'ah or from human reasoning.
  3. Some are general linguistic rules which the scholars of al Usul developed through linguistic research and presented in a crystallized form, such as research dealing with languages and their origins, the classification of words into metaphorical and literal, discussions of etymology, synonymity, emphasis, generalization, specification, the meanings of grammatical particles and so on.
  4. Some are derived from the classical sciences of the Qur'an and the Sunnah, such as discussions concerning the transmission of Hadith by a single narrator Ahad, or by an impeccable plurality of narrators Tawatur, the non-standard recitations of the Qur'an and the rules about them, the criteria for the acceptance Ta'dil or rejection Jarh of narrators of Hadith, abrogation of legislation al Nasikh wa al Mansukh3, the condition of the text of a Hadith and its chain of narrators, and so on.
  5. Finally, the examples cited by the scholars of al Usul in illustration of their arguments are derived from the specifics of Fiqh, and from the detailed evidence for the same as taken from the Qur'an and the Sunnah.

The issues with which the scholars of al Usul are primarily concerned include the following:


It is difficult to attempt a study of Usul al Fiqh and its development without considering the history of Fiqh, the practical precepts of Shari'ah that have been gleaned from detailed source-evidence.

The lexical meaning of Usul is foundation, or basis Asl; plural Usul or that upon which something else is built. In the legal system of Islam, Fiqh is built upon and stems from the bases Usul which constitute its source-evidence. Hence, in order to understand the origins of Usul al Fiqh, we need to have a general idea of the history of Islamic legislation Tashri'.

Establishing Shari'ah legislation, prescribing law, laying down rules and regulations, and defining systems is a function which is specific to Allah alone. Anyone who presumes to ascribe these functions to any other than Allah commits the sin of al Shirk, as, in doing so, he has effectively contradicted the belief in the Oneness of Allah Tawhid.

Allah has provided articulate proofs and clear source-evidence in order that the believers should have no trouble in finding their way to the particulars of His legislation, or Ahkam. with reference to some of this source-evidence, the Islamic Ummah has agreed on its validity and its relevance to the Ahkam, and has accepted it as such. However there are differences with regard to other source-evidence.

The source-evidence upon which the whole Ummah fully agrees, and on the validity of which there is general consensus, comprises the two sources that formed the basis of legislation at the time of the Prophet (s). These two sources of legislation are:

1. The Qur'an: This may be defined as the words revealed to the Prophet (s) the recitation of which itself constitutes an act of worship, the shortest Surah of which is a challenge to mankind to produce anything the like thereof, every letter of which has been transmitted to us via an indisputably authentic chain of authority Tawatur; which is written between the two covers of the Holy Book Mushaf beginning with Surat al Fatihah "The Opening Chapter" and ending with the Surat al Nas.

2. The Sunnah: This includes everything, other than the Qur'an, which has been transmitted from the Prophet(s); what he said, did, and agreed to.

Thus, every utterance of the Prophet (s), apart from the Qur'an, and his every deed, from the beginning of his mission to the last moment of his life, constitute his Sunnah, in the general sense of the word, whether these establish a ruling which is generally applicable to all members of the Ummah, or a ruling which applies only to the Prophet himself or to some of his Sahabah.

Regardless of whether what the Prophet (s) did was instinctive or otherwise, his every word, deed and approval may be taken as the basis for evidence in a legal ruling. This is so regardless of whether his utterances or actions related to matters of faith or practice, or whether they were concerned with commanding or recommending, prohibiting, disapproving, or allowing; and regardless of whether his word or action was based on a ruling previously revealed in the Qur'an, or whether it served independently to establish legislation.

During the lifetime of the Prophet (s), all the legal rulings Ahkam of the Shari'ah, inclusive of all of its classifications, such as principal and derived rulings, teachings on the fundaments of the faith, and regulations regarding personal practice and legalities, were derived from these two sources, the Qur'an and the Sunnah.

3. Ijtihad was practiced by the Prophet (s) and by those of his companions with legal proclivities Ahl al Nazar. The Prophet's Ijtihad was sometimes confirmed by the Qur'an and sometimes not; in which case it was explained that the better solution was other than that which he had adopted.

The Ijtihad made by the Companions was always in response to situations which actually occurred to them. Later, when they met the Prophet (s), they would explain what happened and tell him what they had decided. Sometimes he (s) approved of their Ijtihad , and such decisions of theirs (having gained the approval of the Prophet) became a part of the Sunnah. If he (s) disapproved of their Ijtihad , his explanation of the correct procedure would become the Sunnah.

Thus, we can say that at that stage legislation depended on the two forms of Divine revelation Wahy:

  1. Recited revelation Wahy Matlu; or the Qur'an with its absolute inimitability I'jaz
  2. Non-recited revelation Wahy Ghayr Matlu; or the Sunnah of the Prophet (s)

Indeed, the Ijtihad made by the Prophet (s) set a precedent for his Sahabah and later Muslims, that clearly proved the legitimacy of Ijtihad , so that when they could not find an express legal ruling in the Qur'an or Sunnah, they were to make use of Ijtihad in order to arrive at a judgement on their own.

Moreover; probably to reinforce and establish this concept, the Prophet (s) used to order certain of his Companions to make Ijtihad concerning certain matters in his presence. Then he would tell them who was correct and who was mistaken.


As to the Qur'an..

The Qur'an was learned and understood by the Sahabah without their ever having recourse to formal rules of grammar. Likewise, endowed as they were with clear vision, sharp wits and common sense, they readily understood the aims of the Lawgiver and the wisdom behind His legislation.

Indeed, the Sahabah rarely used to question the Prophet (s) about any matter unless he himself mentioned it first.

It is reported that Ibn Abbas said: "I have never seen any people better than the Sahabah of the Prophet, may Allah bless him and grant him peace. Throughout his mission, until he passed away, they only asked him about thirteen matters, all of which are mentioned in the Qur'an. For example, [the meaning of]: 'They ask you about fighting in the sacred month...' (2:212); and 'They ask you about the menstruating woman...' (2:222)" Ibn Abbas said, "They only asked him about matters which were of actual concern to them."4

Ibn 'Umar said in this respect: "Don't ask about something that hasn't happened, for I heard my father, 'Umar ibn al Khattab, curse one who asked about something which had not occurred."5

Qasim said (to the third generation of Muslims): "You ask about things we never asked about, and quarrel about things we never quarrelled about. You even ask about things which I'm not familiar with; but if we did know, it would not be permitted for us to remain silent concerning them."6

Ibn Ishaq said: "I met more of the Prophet's Sahabah than anyone else did; and I have never seen a people who lived more simply, or who were less demanding on themselves."7

'Ubadah ibn Nusay al Kindi said: "I have known a people whose austerity was not as rigid as yours, and whose questions were quite other than the ones you ask."8

Abu 'Ubaydah said in his book Majaz al Qur'an: "It has never been reported that any of the Sahabah went to the Prophet (s) for knowledge of anything which could be found in the Qur'an."9

As to the Sunnah...

The parts of the Sunnah which consist of the Prophet's words were in the Companions' own language, so they knew its meaning and understood its phrases and context.

As far as the Prophet's deeds were concerned, they used to witness them, then tell others exactly what they had seen. For example, hundreds of people saw the Prophet (s) making ablutions Wudu' and then adopted his practice without asking him about details; like which of the various actions in Wudu' were obligatory and which were recommended, which were merely allowed and which were not. Likewise, they witnessed him (s) performing Hajj and Salah, and the other acts of worship.

People were heard asking the Prophet (s) to give Fatawa concerning various matters, and he did so. Cases were referred to him, and he would pronounce his judgement. Problems would arise amongst the Sahabah, and he would give a definite answer; whether the problems concerned mutual relations, personal conduct, or various political matters. They witnessed all these situations and they understood the context in which they took place, so that the wisdom and purposes of the Prophets judgements were not hidden from them.

People also saw how the Prophet (s) used to notice the conduct of his Sahabah and others. Thus, if he (s) praised anybody, they knew that the person's act had been a good one; and if he (s) criticized anybody, they knew that there had been something wrong with what the person had done.

Moreover, all the reports concerning the Prophet's Fatawa, rulings, decisions and approval or disapproval of various matters indicate that they took place in the presence of many people. So, just as the colleagues of a doctor know, due to their long association and experience10, the reasons for his prescribing certain medicines, so also the Sahabah of the Prophet (s) knew exactly the reasoning behind his decisions.

As to Ijtihad ...

The indications that Ijtihad is valid and relevant in the contemporary context are many. For example, Mu'adh ibn Jabal states that when the Prophet (s) sent him to Yemen, he asked:

"what will you do if a matter is referred to you for judgement?" Mu'adh said: "I will judge according to the Book of Allah." The Prophet asked: "what if you find no solution in the Book of Allah?" Mu'adh said: "Then I will judge by the Sunnah of the Prophet." The Prophet asked: "And what if you do not find it in the Sunnah of the Prophet?" Mu'adh said: "Then I will make Ijtihad to formulate my own judgement." The Prophet patted Mu'adh's chest and said "Praise be to Allah who has guided the messenger of His Prophet to that which pleases Him and His Prophet."11

This Ijtihad and forming of one's own judgement, as mentioned by Mu'adh, is further explained in the advice 'Umar gave to Abu Musa when he appointed him a judge: "Judgement is to be passed on the basis of express Qur'anic imperatives or established Sunnah practices.." Then he added:

"Make sure that you understand clearly every case, that is brought to you for which there is no applicable text of the Qur'an or the Sunnah. Yours, then, is a role of comparison and analogy, so as to distinguish similarities -in order to reach a judgement that seems nearest to justice and best in the sight of Allah."12

Consequently, al Imam al Shafi'i explained "opinion" as meaning Ijtihad , and Ijtihad as meaning al Qiyas. He said: "They are two names for the same thing."13

Abu Bakr al Siddiq, Khalifat Rasul Allah, said: "As far as the Prophet is concerned, his opinion was always correct because Allah always guided him. In our case, however, we opine and we conjecture."14

Thus, we may state that the concept of Ijtihad or "opinion", at that stage, went no further than one of the following:

  1. Applying one or another of the possible meanings in cases where a sentence may lend itself to two or more interpretations, e.g. when the Prophet (s) ordered the Muslims to pray among Banu Qurayzah.15
  2. Comparative Qiyas; which deals with a matter by comparing it with another, similar matter which is dealt with in the Qur'an or Sunnah. For example, the Qiyas of 'Ammar who compared the case of Tayammum when in a state of Janabah to Ghusl, and therefore rubbed his whole body with dust.16
  3. Ijtihad by taking into account something which is potentially beneficial; or prohibiting something which could lead to wrongdoing; or deriving a particular ruling from general statements; or adopting a specific interpretation; and so on.

The extent of the Prophet's concern with encouraging the Sahabah to make Ijtihad and training them in its use can be seen in his saying "When a judge makes Ijtihad and reaches a correct conclusion, he receives a double reward; and if his conclusion is incorrect, he still receives a reward."17

The Ijtihad of many of the Sahabah was so accurate that in many cases the revelations of the Qur'an confirmed it, and the Prophet (s) supported it. Obviously, their close association with the Prophet (s) had afforded them a keen sense of the aims of the All-wise Lawgiver, of the basic purposes behind the Qur'anic legislation, and of the meanings of the texts; opportunities which those who came after them did not directly enjoy.