Ijma in the context of "Shafi'ism"

Sunni Islam is the largest branch of Islam and the largest religious denomination in the world. It holds that Muhammad did not appoint any successor and that his closest companion Abu Bakr (r. 632–634) rightfully succeeded him as the caliph of the Muslim community, being appointed at the meeting of Saqifa. This contrasts with the Shia view, which holds that Muhammad appointed Ali ibn Abi Talib (r. 656–661) as his successor. Nevertheless, Sunnis revere Ali, along with Abu Bakr, Umar (r. 634–644) and Uthman (r. 644–656) as 'rightly-guided caliphs'.

The term Sunni means those who observe the sunna, the practices of Muhammad. The Quran, together with hadith (especially the Six Books) and ijma (scholarly consensus), form the basis of all traditional jurisprudence within Sunni Islam. Sharia legal rulings are derived from these basic sources, in conjunction with consideration of public welfare and juristic discretion, using the principles of jurisprudence developed by the four legal schools: Hanafi, Hanbali, Maliki and Shafi'i.

Sharia (/ʃəˈriːə/; Arabic: شَرِيعَة, romanized: sharīʿah, lit. 'path [to water]', IPA: [ʃaˈriːʕa]), also transliterated as Sharī'ah, Shari'a, or Shariah, is a body of religious law that form the Islamic tradition based on scriptures of Islam, particularly the Qur'an and hadith. In Islamic terminology sharīʿah refers to immutable, intangible divine law, in contrast to fiqh (Islamic jurisprudence), which refers to its interpretations by Islamic scholars. Sharia, or fiqh as traditionally known, has always been used alongside customary law from the very beginning in Islamic history; it has been elaborated and developed over the centuries by legal opinions issued by qualified jurists – reflecting the tendencies of different schools – and integrated with various economic, penal and administrative laws issued by Muslim rulers; and implemented for centuries by judges in the courts until recent times, when secularism was widely adopted in Islamic societies.

Traditional theory of Islamic jurisprudence recognizes four sources for al-sharia: the Qur'an, sunnah (or authentic ahadith), ijma (lit. consensus) (may be understood as ijma al-ummah (Arabic: إجماع الأمة) – a whole Islamic community consensus, or ijma al-aimmah (Arabic: إجماع الائـمـة) – a consensus by religious authorities), and analogical reasoning. It distinguishes two principal branches of law, rituals (Ibadah) and social dealings (Muamalat); subsections family law, relationships (commercial, political / administrative) and criminal law, in a wide range of topics assigning actions – capable of settling into different categories according to different understandings – to categories (ahkam) mainly as: mandatory, recommended, neutral, abhorred, and prohibited. Beyond legal norms, Sharia also enters many areas that are considered private practises today, such as belief, worshipping, ethics, clothing and lifestyle, and gives to those in command duties to intervene and regulate them.

Ijtihad (/ˌɪdʒtəˈhɑːd/ IJ-tə-HAHD; Arabic: اجتهاد ijtihād [ʔidʒ.tihaːd], lit. 'physical effort' or 'mental effort') is an Islamic legal term referring to independent reasoning by an expert in Islamic law, or the thorough exertion of a jurist's mental faculty in finding a solution to a legal question. It is contrasted with taqlid (imitation, conformity to legal precedent). According to classical Sunni theory, ijtihad requires expertise in the Arabic language, theology, revealed texts, and principles of jurisprudence (usul al-fiqh), and is not employed where authentic and authoritative texts (Qur'an and hadith) are considered unambiguous with regard to the question, or where there is an existing scholarly consensus (ijma). Ijtihad is considered to be a religious duty for those qualified to perform it. An Islamic scholar who is qualified to perform ijtihad is called a "mujtahid".

For the first five centuries of Islam, the practice of ijtihad continued in theory and practice among Sunni Muslims. It then first became subject to dispute in the 12th century. By the 14th century, development of classic Islamic jurisprudence or fiqh prompted leading Sunni jurists to state that the main legal questions in Islam had been addressed, and to call for the scope of ijtihad to be restricted. In the modern era, this gave rise to a perception amongst Orientalist scholars and sections of the Muslim public that the so-called "gate of ijtihad" was closed at the start of the classical era. While recent scholarship established that the practice of Ijtihad had never ceased in Islamic history, the extent and mechanisms of legal change in the post-formative period remain a subject of debate. Differences amongst the Fuqaha (jurists) prevented Sunni Muslims from reaching any consensus (Ijma) on the issues of continuity of Ijtihad and existence of Mujtahids. Thus, Ijtihad remained a key aspect of Islamic jurisprudence throughout the centuries. Ijtihad was practiced throughout the Early modern period and claims for ijtihad and its superiority over taqlid were voiced unremittingly.

The Hanafi school or Hanafism is the largest school of Islamic jurisprudence out of the four principal schools within Sunni Islam. It developed from the teachings of the jurist and theologian Abu Hanifa (c. 699–767 CE), who systemised the use of reasoning (ra'y). Hanafi legal theory primarily derives law from the Quran, the sayings and practices of Muhammad (sunnah), scholarly consensus (ijma) and analogical reasoning (qiyas), but also considers juristic discretion (istihsan) and local customs (urf). It is distinctive in its greater usage of qiyas than other schools.

The school spread throughout the Muslim world under the patronage of various Islamic empires, including the Abbasids and Seljuks. The region of Transoxiana emerged as a centre of classical Hanafi scholarship between the 10th and 12th centuries, which gave rise to the Maturidi school of theology. The Ottoman Empire adopted Hanafism as its official school of law and influenced the legal thought of the school, eventually codifying it as the Mecelle in the 1870s.

Principles of Islamic jurisprudence (Arabic: أصول الفقه, romanized: ʾUṣūl al-Fiqh) are traditional methodological principles used in Islamic jurisprudence (fiqh) for deriving the rulings of Islamic law (sharia).

Traditional theory of Islamic jurisprudence elaborates how the scriptures (Quran and hadith) should be interpreted from the standpoint of linguistics and rhetoric. It also comprises methods for establishing authenticity of hadith and for determining when the legal force of a scriptural passage is abrogated by a passage revealed at a later date. In addition to the Quran and hadith, the classical theory of Sunni jurisprudence recognizes secondary sources of law: juristic consensus (ijmaʿ) and analogical reasoning (qiyas). It therefore studies the application and limits of analogy, as well as the value and limits of consensus, along with other methodological principles, some of which are accepted by only certain legal schools (madhahib). This interpretive apparatus is brought together under the rubric of ijtihad, which refers to a jurist's exertion in an attempt to arrive at a ruling on a particular question. The theory of Twelver Shia jurisprudence parallels that of Sunni schools with some differences, such as recognition of reason (ʿaql) as a source of law in place of qiyās and extension of the notions of hadith and sunnah to include traditions of the imams.