Well the paragraph you mentioned is talking about one of the sources or let me say tools of the sources of the Maliki Madhab: customs and practices of the people of Medina! So i would recommend you to read more about it in wikipedia (there are more details in the Arabic part especially when it comes to the customs and practices of the people of Medina if you can read Arabic)!
Well let me first explain when this "tool" springs into action:
Of course as any other Madhab the Maliki have two primary sources: The Quran and Sunna, and they have many levels (which i won't and can't explain in this Answer) in each of these sources but both are part of the so called transfer sources (using your translation) الأصول النقلية these are sources based on a narrator chain!
On the other hand the Maliki school has also rational sources الأصول العقلية like Qiyas, Istihssan, Istislah etc.
However the customs and practices of the people of Medina (al-Madina, al-Medina) are part of that what you might call transfer sources they are used in a rational manner like via Qiyas:
for example if there's a hadith ahad which goes ahead with the consensus of the fuqaha' of al-Medina among the sahaba and the tabi'yn then this would support this hadith and this hadith would be accepted.
But if there's no consensus among those fuqaha' of al-Medina then any opinion of them could be more or less equal if it has no support, so it would be a matter of ijtihad to whether accept or reject this hadith.
So first of all one should know that those people who count as Ijma' for ahl al-Madina are only the scholars from the sahaba and tabi'yn who lived in al-Medina and from whom the fatwas and opinions were well known among later scholars there.
And now i come to those statements:
- الإجماع على النقل If on a matter it was common sense to give a specific fatwa then this would be regarded as an Ijma' naqli which means it was narrated that all scholars have (somehow) agreed about this fatwa either by a clear Ijma' إجماع صريح or maybe some of them didn't reject this fatwa (so it was at least partly a silent Ijma' إجماع سكوتي).
But i think calling this a transfer Ijma' is not that exact as a translation i would recommend: transmission, pass on/down, traditional (which also is not that good) or communicated Ijma'
So it's an Ijma' which has been narrated with some kind of tawatur to use a term from hadith sciences! For example the way they practice Adhan(each sentence 2 times, repeating the two shada with a higher voice twice, without prolongation etc.), Iqama and prayer times so this is a custom which has some tradition, Qadi 'Iyad explained it with more details نقل refers:
- to a anything that our Messenger (peace be upon him) practiced or asked people to do.
- or to anything which was narrated that he didn't change (acceptance).
- or to anything which was narrated that he left or didn't do (rejection)
- or a transfer of things or locations like for his grave, his minbar (peace be upon him) etc.
- إجماع في الرأي Here we discuss the matter when it comes to one opinion or different opinions in confrontation with a hadith ahad. In Brief: In the case of a conflict in which different opinions occur then Ijtihad is needed and opinions would be rejected or accepted according to the tools of Ijtihad! But about this kind of Ijma' there are different opinions among the madhab itself and some scholars also call it إجماع استدلالي.
According to Qadi 'Iyad there are 3 possibilities (see also my explanation above):
- Either the ahad and the customs and practices of people of al-Madina agree and are in line then it would be a support of the sanity of this hadith if this Ijma' came through transmission or if it was based on an opinion (Ijtihad) this would favor this hadith if there's no different opinion. If not Qiyas and Ijtihad would be necessary.
- If there's an other different ahad which is supported by the customs and practices of people of al-Madina they would favor the ahad which is in line with their customs in case of a conflict.
- If there's a consensus through transmission they reject an ahad which is in conflict to this custom because they would have tawatur vs. ahad, and tawatur is more likely to lead to certainty while ahad is more likely to lead to doubt.
So you maybe see that somehow an Ijma' on opinion doesn't really seem to exist or to be accepted, as mostly they refer to the Ijma' by transmission, which explains that most of them don't accept it as a proof!
I hope i could explain a few things and make it more clear!
You could also read in this Arabic Thread.
And Allah knows best!