Part 3 of a series
The Quran and sunnah are acknowledged as the two primary sources of information about the sharia. Outside of them however, there are numerous secondary sources, of which some are more respected and widely used than others. One secondary source that enjoys common currency and widespread acceptance is ijma, or consensus.
This should be a familiar topic to anyone familiar with the Western judicial system, where precedent and stare decisis are well known. Ijma follows a similar principle; if the courts have previously agreed on a ruling, it is likely that that ruling is correct. Interestingly, the validity of ijma itself derives from a hadith in which the Prophet said “Allah will never cause my ummah [community] to agree on a mistake.” You can see here how the secondary sources derive their authority from the primary sources.
Of course, the main difference in sharia is that law is not developed by consistently applying certain logical and judicial principles, but is instead discovered by adhering to the message of the Quran and the life of its Messenger. Therefore, it is not enough that Mohammed (pbuh) has generically indicated that consensus is valid; jurists must suss out exactly what is meant by “my ummah” as well as “agree.” Does anyone’s opinion count? Is ijma only reached if every single Muslim agrees? What about every adult? Every man? Every judge? Must they agree in general terms, or specifically, or in whole or in part? Even if you accept that consensus is a valid means by which the Law can be discovered, what constitutes consensus is an open question.
There are many levels of ijma. It can be all Muslims of all times; all Muslims of a particular time; all jurists who are righteous and pious and free of error; all jurists who are free of error, regardless of their righteousness; all jurists in an area; just the companions of the Prophet; and so on. Moreover, ijma can be obtained positively, with each jurist speaking out in favor of an interpretation, or it can be obtained by silence, where a jurist sees his fellows reach a conclusion and does not remark on it.
Moreover, even if you agree on what constitutes ijma and what type of ijma is valid, jurists disagree on what level of authority a ruling based on ijma is granted. Is it conclusive, bearing the same weight as an explicitly worded passage from the Quran or perfectly narrated hadith? Is it an argument in favor of a position, but not probitive? Is ijma of the companions of Mohammed (pbuh) proof, but not otherwise? Is explicit ijma proof, but silent ijma not? If we have records of many rulings, but not of their basis, does the ijma of the rulings by itself generate a basis for a new ruling?
Obviously, a great deal of controversy exists about how to apply ijma to the sharia. This article is meant merely as an introduction and does not take a position on this issue. When we deal more deeply with specific scholars or schools of thought, we will explore what they think of ijma. If you do not accept a ruling based on ijma because you find the reasoning faulty, though, what does that make you? Is it heresy (kufr)? Again, on this topic, opinions vary. Mostly, though, it is not considered heresy — unless the ijma is one of the Prophet’s companions, or one with continuity throughout all previous generations of Muslims, or on topics dealing with fundamentals of Muslim life (like the Five Pillars, prohibition of murder and theft, etc).
There is no completely uncontroversial argument for the authority of ijma. In fact, the premise that the ijma of a majority is binding is not actually accepted by a majority of jurists, and therefore is not proved by ijma! Regardless, ijma serves an important function. The purpose of the sharia is to both guide the individual and guide the community. Just as it applies to the behavior of an individual person, it applies to Islamic society as a whole. Ijma is important in generating standards of behavior which can be applied to the whole of Islamic society. Therefore, even if it cannot be held to the same level of authority as Quran and sunnah, it is an important tool for building a comprehensive Islamic jurisprudence.
As always, if you have comments, thoughts, or questions, please let me know. I strive to be as accurate as possible in dealing with a complex and sometimes controversial subject.