Ijma

Ijma (Arabic: إجماع, romanized: ijmāʿ, lit. 'consensus', IPA: [ʔid͡ʒ.maːʕ]) is an Arabic term referring to the consensus or agreement of the Islamic community on a point of Islamic law. Sunni Muslims regard it as one of the secondary sources of Sharia law, after the Qur'an, and the Sunnah. Exactly what group should represent the Muslim community in reaching the consensus is not agreed on by the various schools of Islamic jurisprudence. Some believe it should be the Sahaba (the first generation of Muslims) only; others the consensus of the Salaf (the first three generations of Muslims); or the consensus of Islamic lawyers, the jurists and scholars of the Muslim world, i.e. scholarly consensus; or the consensus of all the Muslim world, both scholars and lay people. The opposite of Ijma (i.e., lack of consensus on a point of Islamic law) is called ikhtilaf.

Imam Al-Shafi'i was once approached by an old man who asked for proof of Ijma from the Quran. Imam Al-Shafi'i went home and recited the whole Quran three times. On the third recitation, he found a verse in Sura An-Nisa (4:115)

"And whoever defies the Messenger after guidance has become clear to them and follows a path other than that of the believers, We will let them pursue what they have chosen, then burn them in Hell—what an evil end!"

which mentions the word 'Sabeelil Mu'mineen' (the way of those of faith). Imam Al-Shafi'i told the old man this verse was a proof for Ijma from the Quran and he was satisfied. Another proof of Ijma from the Quran is in Surah Luqman (31:15) in which Allah mentions

"and follow the way of those who turn to Me in devotion"

Another proof of Ijma in the Quran is in Sura an-Nisa (4:83) in which Allah mentions

"And when they hear news of security or fear, they publicize it. Had they referred it to the Messenger or their authorities, those with sound judgment among them would have validated it. Had it not been for Allah’s grace and mercy, you would have followed Satan—except for a few."

Some scholars have the opinion that Surah Al Fatihah verse 1:6 and 1:7 which Muslims read at least 17 times a day (in their 5 daily Salah) is also an indirect support of Ijma.