The Arabic word Ijma is agreeing on something.
Linguistically it carries two meanings:
1. Agreement - you say, “the people agreed on something.” If they come together and agree and this cannot come about except from a group.
2. Firm determination - It is said, “Someone has made his opinion firm on such a matter,” if he is determined to it and this can come about by one person or by a group.
Technically, it means: The agreement of all scholars worthy of making legal decisions from the Ummah of Muhammad (May Allah Honour him and Grant him Peace) after his death on a religious matter in any period in time.
Examples of Ijmaa‘
1. They agreed that the divorced woman from a revocable divorce during her waiting period is entitled to adequate financial support and residence.
2. They agreed that sexual intercourse nullifies I‘tikaaf (seclusion in Masjid).
3. They agreed that committing a major sin and openly committing minor sins are injurious by which one’s evidence can be rejected.
4. They agreed that the grandmother does not inherit with the presence of the mother.
5. They agreed that the legacy (will) for an inheritor is not possible.
6. They agreed that there is no blood retribution on one who kills accidentally.
7. They agreed that the divorced woman in a revocable divorce can be inherited by her husband and she can inherit from him so long as she is in her waiting period.
8. They agreed that the journey of a woman in which she is allowed to travel with her husband or a Mahram (one who cannot marry her) is permissible.
9. They agreed that the slaughtering of cattle in the sacred place and by a Muhrim (one in the state of restrictions during Hajj or ‘Umrah) is lawful.
10. They agreed that there are not more than fifteen prostration verses in the al-Qur’aan.
11. They agreed that the menstruating woman must make up for the days she has missed during her menses.
12. They agreed that it is not permissible to fast for someone who is alive.
Proof That Ijmaa’ Is Evidence (In Islaam)
1. Allaah’s words in al-Qur’aan
“If anyone contends even after guidance has been plainly conveyed to him and with the Messenger follows a path other than that becoming to men of faith, we shall leave him in the path he has chosen and make him enter - Hell - what an evil refuge!” (Soorah an-Nisaa’, 4:115)
Allaah the Supreme has warned those who follow a path other than that of the Believers with punishment so it becomes incumbent to follow their way. What is this save an evidence!
2. The saying of the Prophet
“A group of my followers will always remain on the right path.” (Sahih Al-Bukhari, vol. 9:552)
So if the people of a particular time agreed on something evil, it would have negated the correctness of this Hadeeth in that time due to the absence of supporters of the truth and this is invalid. Therefore, invalid too is the possibility of their agreeing on what is contrary to the truth.
Legal Evidence of Ijmaa‘
Ijmaa‘ cannot be valid except of its legality from al-Qur’aan and Sunnah. Some (scholars) are of the opinion that it is valid on the basis of Ijtihaad (independent judgment in a theological question).”
So when Islaam came, it was acknowledged by the Prophet and as such his companions would travel with other people’s wealth and he did not prevent that the Sunnah in his words, his actions and his acknowledgements. So when he acknowledged that, it became established by the Sunnah.
Categories of Ijmaa‘
Ijmaa‘ is divided into two categories:
1. Ijmaa‘ Qawlee or Fi‘lee (consensus by word or action)
2. Ijmaa‘ Sukootee (consensus by silence)
1. Ijmaa qawlee or fi’lee:-
Each person must clearly state his opinion on the law on which the consensus was taken. Or his actions by themselves prove its permissibility, according to him. In this category of Ijmaa‘ there is no difference as to its proof according to those who opined the establishment of Ijmaa‘.
2. Ijma sukooti:-
Some (scholars) clearly state their opinion or their action and it is publicized but the others remain silent on the word or action or they do not forbid what has taken place.