The Third Daleel: Al-Ijmaa’ (consensus)
The meaning of Al-Ijmaa’:
Al-Ijmaa’ linguistically:
It is the determination or resolve upon a matter and agreement. This resolve is valid to emanate from one (person) and this meaning is found in the Qawl of the Messenger (saw):
“Whoever does not resolve (i.e. intend) the fasting before Fajr, then there is no fasting for him” (related by the compilers of the Sunan).
Just as it is valid to be used for more than one like in His Qawl Ta’Aalaa:
So resolve upon your plan along with your associates (Younus 71).
Which means resolve whilst being in agreement with your associates.