穆斯林普遍曾对众mujtahid进行taqlīd,尽管他们之间存在分歧,因为其分歧的根源在于沙里阿的证据。因此,每位mujtahid对立法者的训示(khitab al-shaari')的理解,对他本人以及跟随他的人而言,都被视为一条沙里阿律例。这是因为立法者的训示即是沙里阿律例(hukm shar'i),而对立法者训示的理解,也是一条沙里阿律例,只是就理解者本人以及遵循其理解的人而言。能够领会立法者训示的人便进行ijtihād;未达到ijtihād水平的人,则在各项律例上追随已达到并实践ijtihād的人。问题不在于个人追随某位faqih,正如问题也不在于遵循某个学派(mazhab)。问题在于采纳faqih所推导出的沙里阿律例并依其行事。因为穆斯林被命令只遵循沙里阿律例并依其行事,而不是遵循某个学派、某个人,或依照某个特定学派行事,也不是追随某个特定的人。当他能够通过自己的ijtihād获得沙里阿律例时,就应当这样做;如果不能,则应采纳他人推导出的律例。在早期,mujtahid的人数可以以千计。因此我们发现,穆斯林所追随的mujtahid并不局限于四家、五家、六家或任何固定数目的学派,事实上学派众多,mujtahid也数量繁多。每个群体都遵循某位mujtahid所推导出的律例,无论此人是否属于某个学派。例如,库法的普通民众依照艾布·哈尼法和苏富扬·al-Thawri的教法裁决行事,而什叶派则遵循Ja'far al-Sadiq的学派。 过去，麦加民众遵循伊本·吉莱只的教法裁决，麦地那民众遵循马立克的教法裁决，巴士拉民众遵循奥斯曼的教法裁决，沙姆民众遵循奥扎伊的教法裁决，埃及民众遵循伊本·萨德的教法裁决，呼罗珊民众遵循阿布杜拉·伊本·穆巴拉克的教法裁决，也门的部分民众遵循宰德·伊本·侯赛因的教法裁决。许多穆斯林追随赛义德·伊本·穆塞耶卜、伊本·阿比·莱莱、伊克里马、拉比尔·艾尔-拉伊、穆罕默德·伊本·沙哈卜·祖赫里、哈桑·巴士里、莱斯·伊本·萨德、苏菲扬·伊本·欧耶奈、伊斯哈格·伊本·拉胡耶、艾布·绪尔、达乌德·宰希里、伊本·舍布勒玛和伊本·贾里尔·塔伯里的教法裁决。他们每一位都是穆贾泰希德（独立立法的学者），并各自创立了一个学派（麦资海卜）。这些学派each都有其独特的依据经训进行推理（伊贾提哈德）的方法，以及在教律（阿哈卡姆）上的独特见解（拉伊）。许多穆贾泰希德和伊玛目曾担任各地的法官和统治者。伊玛目、法官和统治者之间的分歧，导致了教律的差异，每人都依自己的见解或所信奉的某位教法学家的见解进行裁决。这使得国家境内出现了不同的判决。因此，有些乌拉玛明显倾向于统一判案所依据的律例，并希望哈里发颁布命令，要求民众遵守。当时，一些了解社会状况的人认为，应当编写一部全面的典籍，供法官和其他人查阅，以减轻法官的负担，并方便诉讼当事人。伊本·穆格法尔就此事致信哈里发曼苏尔，信中提到：

The Muslims generally used to perform Taqlīd to the mujtahidin despite their disagreements since the basis of their disagreements was the Sharī’ah evidence. So the understanding of every mujtahid of the address of the Legislator (khitab al-shaari’) is considered a Sharī’ah rule with respect to him and with respect to the one who makes Taqlīd to him. This is because because the address of the Legislator is the hukm shar’i (Sharī’ah rule) and the understanding of the Legislator’s address is a Sharī’ah rule but in respect to the one who understood it and in respect to the one who follows him in this understanding. Those who attained the understanding of the Legislator’s address used to perform Ijtihād. Those who did not reach the level of Ijtihād used to follow, in ahkām (rules), those who had reached the level of Ijtihād and practised Ijtihād. The issue was not that of following the faqih personally just as the issue is not one of making Taqlīd to a mazhab. Rather, the issue is about adopting the hukm shar’i deduced by the faqih and acting upon it. Since, the Muslim is ordered to follow the Sharī’ah rule only and act upon it and not follow a mazhab or person or act according to any particular mazhab or follow any particular person. When he is able to reach the hukm shar’i through his own Ijtihād he should do that, if not he should adopt a hukm deduced by someone else. In the early ages the mujtahidin could be counted by the thousands. That is why we find that the mujtahidin whom the Muslims used to follow were not restricted to four, five, six or any number of mazhabs, in fact there were many mazhabs and numerous mujtahidin. Each group used to follow rules deduced by a mujtahid whether he was from a mazhab or not. For example, the general population of Kufa acted upon the fatwa of Abu Hanifah and Sufyan al-Thawri but the Shi’a used to act upon the mazhab of Ja’far al-Sadiq. The practise of the people of Makkah used to be according to the fatwa of Ibn Jurayj and the people of Madina on the fatwas of Malik and the people of Basra on the fatwas of ‘Uthman and the people of al-Sham on the fatwas of al-Awza’i and the people of Egypt on the fatwas of Ibn Sa’d, and the people of Khurasan on the fatwas of ‘Abd Allah ibn al-Mubarak and some of the people of Yemen on the fatwas of Zayd ibn al-Husayn. Many of the Muslims used to follow the fatwas of Sa’id ibn al Musayyab, Ibn Abi Layla, ‘Ikrama, Rabi’i Ar-Ra’i, Muhammad ibn shihaab Az-Zuhri , Hasan Al Basari, Laith ibn sa’ad, Sufyan Ibn ‘Uyayna, Ishaq ibn Rahawiya, Abi Thawr, Dawud Az-Zahiri, Ibn shibrima and Ibn Jarir At-Tabari. Each of them was a Mujtahid and lead a mazhab. Each of the mazhabs from these mazhabs had a particular methodology in Ijtihād and a particular ra’i (opinion) in the ahkam. Many of the Mujtahidin and Imams were judges and rulers in the lands. The differences among the imams and the judges and rulers lead to a difference in the ahkam (rules), each one judged with his own opinion or according to the opinion of a faqih whose opinion he held. This resulted in the presence of different judgements in the state, due to this there were ‘Ulamā who were obviously inclined towards unifying the ruling by which judgement is given and wanted the Khalifah to issue an order for people to adhere to it. At that time, certain people who knew about the situation of the society took the view that a comprehensive book should be written to which judges and other should refer, so as to lighten the burden of the judges and make it easy for the litigants. Ibn al-Muqaffa’ wrote a letter to the Khalifah al-Mansur regarding this matter, in which it was mentioned:

然而,曼苏尔虽然对这封信印象深刻,却并未采纳其中的建议。于是他着手让法学家和圣训学者将所传承的内容记录下来,以便民众有可以查阅的依据。曼苏尔之所以没有采纳伊本·穆卡法而提出的意见——即为国家制定宪法与典章,使民众在具体的律例上趋于统一——其原因在于他与马立克之间发生的一件事。伊本·萨阿德在《诸阶层传》中记载,马立克·本·艾奈斯说:

However, al-Mansur did not act upon this letter although he was impressed by it. So he took steps to make the Fuqaha and the muhaddithin record what has reached them until people had references to which they could refer. The reason for al-Mansur not acting upon the opinion of Ibn al-Muqaffa’ in laying down a constitution and canons for the state which would have brought the people together on specific ahkāms was what transpired between him and Malik. Ibn Sa’ad narrates in al-Tabaqat that Malik bin Anas said:

因此,各派教法和诸多观点未能统一,伊jtihād与ra’y仍留存于人们之中,各人依自己认为正确的裁定而行。法官与统治者也保留着依其认为适当的标准作出裁决的权利。正因如此,每位教法学家都有学生前来学习他的观点,阐释其教法学派,而对这一分歧的看法也随之改变,它终于发展成为一门独立的学问,人们称之为“分歧学”(‘ilm al-khilaf)。人们像研习法源学(usul al-fiqh)那样研习它。他们说,众伊玛目之间的分歧是一种仁慈。每位伊玛目的学生都会对具体教法条文(furu’)加以阐发。正是这种阐发保存了某些mujtahid的教法学派,也导致了另一些学派的消亡。al-Awza’i、al-Hasan al-Basri、al-Thawri和Ibn Jarir al-Tabari是知识广博、精通伊jtihād的伟大伊玛目之列,然而他们并未在具体条文上加以阐发,而只局限于法源,而且他们没有阐述其学派立场的学生,因此他们的主张未被遵行,也没有传播开来。至于其余的伊玛目,如Abu Hanifah、Ja’far al-Sadiq、Zayd ibn al-Husayn、al-Shafi’i、Ahmad ibn Hanbal和Malik,他们都有学生和追随者,因此他们的学派得以记录并延续下来。尽管Abu Ja’far al-Mansur对Ja’far al-Sadiq及阿里家族其他人实施了限制,Ja’far al-Sadiq仍推导出了各种律例,并有来自什叶派及其他派别的学生。他们记录下他的见解,并视之如同逊奈一般。他的学派在世界许多地区传播开来。Abu Hanifah有许多学生,最为人熟知的是Abu Yusuf、Muhammad ibn al-Hasan al-Shaybani和Zufar。他们都和Abu Hanifah一样是mujtahid。尽管他们把自己的见解与他的混合在一起,但记录Abu Hanifah学派的功绩应归于他们。Imam Malik的情况也是如此。 他曾居住在麦地那;他有许多学生,以考订圣训及传述者而广为人知,尤其是在《穆宛塔》一书方面。他之后的学生会记录他的教令,阐发枝节问题(furu')并就各类问题提出自己的见解。尽管马立克名声显赫,传播其学派(mazhab)的功劳却归于他的学生。至于沙斐仪,他凭借自身之力在法源学(usul al-fiqh)上确立了崇高的声望,这从其巨著《乌姆》以及《论纲要》(al-Risala)和《驳斥善断》(Ibtal al-Istihsan)中可以看出,这些著作是那个时代理性觉醒的最杰出范例。他的学生如拉比尔和穆扎尼,遵循这一方法,研读他的见解,拓展了他的学派,因此它传播得十分广泛。同样,对于艾哈迈德·本·罕百勒而言,尽管圣训在其学派中占据主导地位,他仍有学生为他拓展学派、研习他的见解。这些学生首先应当受到推崇,他们不仅传播了其师长与教法家的学派,还阐释教法,并使其兴盛,直至他们所处的时代被认为比教法家的时代更加光辉。因为正是在这一时期,对教律的注释和对证据的阐明得以进行,法学家们由此争相研习教法并加以阐释,尤其是作为教法真正基础的法源学。教法的境况持续传播,直至大为繁荣。其繁盛的顶峰出现在伊历第四世纪,即各学派形成一个世纪之后。

Owing to this, the mazhabs and opinions were not unified and Ijtihād and ra’i remained with the people in adopting the hukm they deemed correct. And the choice remained for judges and rulers to judge with what they deemed as appropriate. Due to this each imam of fiqh has students who came to study their opinions and explain his mazhab and the outlook towards this disagreement which took place changed and it became a science in its own right, they called it the science of disagreement (‘ilm al-khilaf). They studied it just as they studied usul al-fiqh. They said that the disagreement of the imams was a mercy. The student of each imam used to expand on the furu’ (branches of fiqh). It was this expansion which preserved the mazhabs of certain mujtahidin and was the reason for the extinction of others. Al-Awza’i, al-Hasan al-Basri, al-Thawri and Ibn Jarir al-Tabari are some of the greatest imams in terms of their breadth of knowledge and Ijtihād. However they did not expand in furu’ rather confined themselves to the usul and they did not have students who would expound the position of their mazhab, that is why they were not acted upon and they did not spread. As for the rest of the imams such as Abu Hanifah, Ja’far al-Sadiq, Zayd ibn al-Husayn, al-Shafi’i, Ahmad ibn Hanbal and Malik, they had students and followers, so their mazhabs were recorded and continued to exist. Despite the restrictions imposed by Abu Ja’far al-Mansur on Ja’far al-Sadiq and others from the family of ‘Ali he deduced rules and he had students from the Shi’a and others. They recorded his opinions and looked upon them as something akin to the Sunnah. His mazhab spread in many regions of the world. Abu Hanifah used to have many students, the most well known are Abu Yusuf, Muhammad ibn al-Hasan al Shaybani and Zufar. They were all mujtahids like Abu Hanifah. Although they mixed their opinions with his, the credit goes to them for recording the mazhab of Abu Hanifah. The same goes for Imam Malik. He used to reside in Madinah; he had many students who were widely known for scrutinising the hadīth and transmitters of hadīth, especially in regard to the book al Muwatta. His students after him used to record his fatwas and expand on the furu’ and give their views on issues. Despite Malik’s fame the credit for spreading his mazhab goes to his students. As for al-Shafi’i he had established his towering fame by his own hands in usul al-fiqh which is indicated by what comes in the large work al-Umm which along with al-Risala and Ibtal al-Istihsan are the greatest samples of intellectual awakening in that age. His students, such as al-Rabi’ and al-Muzni who proceeded according this method and studied his opinions and expanded his mazhab and so it spread far and wide. Similarly for Ahmad ibn Hanbal, despite the dominant prevalence of hadīth in his mazhab, he had students who expanded his mazhab for him and studied his opinions. The credit first and foremost goes to those students, not only for spreading the mazhab of their teachers and imams but also for the exposition of the fiqh and ensuring that it flourished until their age was considered more radiant than the age of the imams. Since it was in this age that the commentaries of ahkām and clarification of evidences took place, in this way the fuqaha rushed ahead in studying fiqh and explaining it especially the science of usul al-fiqh which is the true basis of fiqh. The situation of fiqh continued to spread until it flourished greatly. The pinnacle of its bloom was in the fourth century A.H, a century after the mazhabs were formed