The Types of Ijma
Ijma Sarih — Explicit Consensus
All qualified scholars of a given generation explicitly agree on a ruling — each one stating their opinion verbally or in writing. This is the strongest form of ijma and, theoretically, the most binding. In practice, it is extremely rare to achieve because the ‘ulama are spread across the Islamic world and rarely gather to explicitly deliberate and vote.
Ijma Sukuti — Tacit Consensus
One scholar (or a small group) issues a ruling, it becomes widely known, and no other qualified scholar in that generation explicitly objects. This “silence implies agreement” position is the most common form of ijma in practice. It is also the most controversial: scholars debate whether silence genuinely implies agreement or might reflect ignorance of the ruling, inability to respond, or simply lack of opportunity.
Ijma al-Sahaba — Consensus of the Companions
The consensus of the Companions of the Prophet (SAW) is considered the most authoritative form of ijma — both because they had direct access to prophetic guidance and because the early Muslim community was small enough that their unanimous agreement is more certain. Many of the foundational rulings of Islamic law (the format of the adhan, the collection of the Quran into a single mushaf, the caliphate succession norms) rest on ijma al-sahaba.
What Ijma Can Establish
Ijma can:
- Confirm a ruling already established in the Quran or Sunnah
- Determine the correct interpretation among competing readings of a text
- Establish the status of something not explicitly addressed in the Quran or Sunnah (through extension of existing principles)
Ijma cannot:
- Override an explicit Quranic text
- Abrogate a ruling directly from a mutawatir hadith
- Establish a new act of ‘ibadah (worship) — ‘ibadah requires textual proof
The Classical Debate
Scholars have debated whether binding ijma is:
- Theoretically possible (given the geographic spread of the ‘ulama) — al-Ghazali and others argued yes
- Practically verifiable in history — difficult to prove definitively
- The correct form: does it require every single scholar, or only the ‘ulama al-ijtihad (qualified mujtahids)?
The most commonly cited “certain” ijma cases: the number of daily prayers (five), the obligatory acts of salah, the basic structure of zakat. These are confirmed by both the Quran/Sunnah AND ijma — so the ijma is secondary confirmation, not the only proof.
The Ismaili Critique
The Ismaili tradition maintains a fundamental critique of ijma as a substitute for prophetic or Imamic authority: the fallibility of human scholars, however qualified, means that their unanimous agreement can still be wrong — particularly on questions of esoteric theology (ta’wil) that require divinely-guided authority to interpret. The living Imam’s nass (designation) provides what ijma cannot: a living, divinely-guided source of authority that is not reducible to scholarly opinion, however widely agreed upon. See [[dai-al-mutlaq-institution]] and [[tawil-esoteric-interpretation]].
See also: Shariah Sources, Fiqh Overview, Fiqh Madhabs, Ijtihad, Qiyas, Dai Al Mutlaq Institution