Regarding the second adhan of 'Uthman, is there a hadith stating that it is necessary for all the Rightly Guided Caliphs to agree on legislation, and not just 'Uthman alone?
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The questioner : Shaykh, regarding the adhan of 'Uthman, if this person were to say that those authorized to legislate are all the Rightly Guided Caliphs,
The Shaykh : Yes
The questioner : and not 'Uthman or one of them alone?
The Shaykh : We would say that you are a foreigner (non-Arab). If he says, "The Sunnah of the Caliphs does not mean they must agree on it; is it a condition?"
The questioner : ... The original rule in speech is generality, O Shaykh?
The Shaykh : No, the Sunnah of the Caliphs is each Caliph individually, yes. Then, as a concession to this, O Zaki, because perhaps you will encounter a stubborn person, and if you tell him, "You are a foreigner," he will say, "You are the foreigner." Tell him: Who remained among the Caliphs in the time of 'Uthman except 'Ali? And 'Ali did not object to it. Yes, yes.
The Shaykh : Yes
The questioner : and not 'Uthman or one of them alone?
The Shaykh : We would say that you are a foreigner (non-Arab). If he says, "The Sunnah of the Caliphs does not mean they must agree on it; is it a condition?"
The questioner : ... The original rule in speech is generality, O Shaykh?
The Shaykh : No, the Sunnah of the Caliphs is each Caliph individually, yes. Then, as a concession to this, O Zaki, because perhaps you will encounter a stubborn person, and if you tell him, "You are a foreigner," he will say, "You are the foreigner." Tell him: Who remained among the Caliphs in the time of 'Uthman except 'Ali? And 'Ali did not object to it. Yes, yes.