«وفي الشريعة: اتفاق المجتهدين من أمة محمد ﷺ في عصر على أمر»
In legal terminology, it is the agreement of the mujtahids of Muhammad’s community ﷺ, in one period, concerning a matter.
The key elements are:
1. Agreement.
2. Participation by mujtahids.
3. Their belonging to the Prophet’s community.
4. Agreement in a given period on a matter.
These qualifications distinguish technical consensus from a public vote or routine committee decision. The book specifically treats the agreement of people qualified in legal reasoning as relevant to its authority.