在圣门弟子的时代，穆斯林自己从《古兰经》和《逊奈》中推导出沙里亚的律例（AHkam shar'aiah）。法官在处理人们之间的纠纷时，会自行推导出他们所面对的每一件事或每一事件的沙里亚裁决（hukm shar'ai）。统治者，从哈里发（Ameer al-Mu'mineen）到各省总督（Wulat）及其他官员，都会亲自推导沙里亚律例，以解决其统治期间出现的每一个问题。 阿布·穆萨·阿尔·阿什阿里和舒赖哈（愿真主喜悦他们）是两位推导律例（AHkam）并依据自己的伊智提哈德（ijtihad）进行裁决的法官（qadi）。穆阿兹·本·哲白勒（愿真主喜悦他）在先知（ﷺ）在世时担任总督（wali），他推导律例，并依据自己的伊智提哈德在其辖区内进行裁决。艾布·伯克尔和欧麦尔（愿真主喜悦他们）都在其执政期间自行推导律例，并且二人都依据各自推导出的伊智提哈德来裁决民众。穆阿维叶和阿慕尔·本·阿绥是两位总督，他们为自己推导律例，依据自己的伊智提哈德，并据此在各自的省份裁决民众。 尽管法官和总督各自进行了伊智提哈德，哈里发有时仍会采纳某些律例，并命令民众执行。那些被要求执行的人必须执行所采纳的规则，并放弃自己对这些规则的见解和伊智提哈德。这是因为沙里亚的律例规定，伊玛目的命令应当公开和秘密地执行。例如，艾布·伯克尔采纳了这样的主张：一次性说三次离婚只构成一次离婚；他还采纳了这样的主张：天课财物应在穆斯林之间平均分配，不论其皈依伊斯兰教的时间早晚，或其他任何因素。穆斯林追随艾布·伯克尔采纳这些主张，法官和总督也都执行了这些规定。此后欧麦尔继任时，他对同样的问题采取了不同的见解。 他强制人们接受并执行一次性说出三次休妻之言即算作三次离婚的裁定，并根据民众入教的先后和实际需要，对财物做出不同的分配。穆斯林们遵从欧麦尔的这些采纳，法官和总督也执行了这些裁定。欧麦尔还采纳了这样一项决定：通过战争获得的土地属于战利品（ghanima），归公库（Bait ul Mal，国库）所有，原有的所有者保留其占有权，而不将土地分配给穆斯林士兵或其他穆斯林。总督和法官遵从了他的这一采纳，并执行了他所采纳的律令。因此，圣门弟子的共识（ijma'a as-sahabah）确认：伊玛目有权采纳某些规定并下令执行，穆斯林必须服从他，即便他们自己的ijtihad（独立判断）与之不同。在著名的伊斯兰教法原则中包括：

During the era of the Companions (sahabah), the Muslims used to extract the AHkam shar’aiah from the Book and the Sunnah by themselves. The judges, when tackling the disputes among people, would deduce by themselves the hukm shar’ai for every issue or event that they were faced with. The rulers, starting with the Ameer al-Mu'mineen to the Wulat and others, would themselves deduce the AHkam shar’aiah to solve every problem that arose during their ruling. Abu-Musa al Ash'ari and ShuraiH (raa) were two judges (qadi) who deduced the rules (AHkam) and judged by their own ijtihad. Mu'adh ibn Jabal (r.a) was a governor (wali) at the time of the Prophet (saw) and used to deduce aHkam and ruled in his wilayah by his own ijtihad. Abu Bakr and Umar (ra) both deduced aHkam by themselves during their ruling and both ruled the people with the ijtihad each of them had deduced. Muawiya and Amr ibn al 'Aas were two governors who deduced aHkam for themselves by their own ijtihad and ruled people in accordance with it in their provinces. In spite of the ijtihad undertaken by the judges and governors, the Khaleefah used to adopt certain aHkam and to order their execution by the people who would be obliged themselves to implement the adopted rules and to leave their own opinion and ijtihad on those rules. This is because the hukm shar’ai states that the Imam's decree is to be executed openly and covertly. Examples of this is Abu Bakr's adoption that the pronouncement of divorce three times in one sitting constitutes only one divorce, and his adoption that funds should be equally distributed among Muslims irrespective of the time when they embraced Islam or any other matter. The Muslims followed Abu Bakr in these adoptions and the judges and governors executed them. When 'Umar came to office after him he adopted different opinions in the same questions. He obliged people to accept and execute the pronouncement of divorce three times in one sitting as three divorces, and he distributed the funds differently according to the time when the people had entered Islam and according to need. The Muslims followed 'Umar in these adoptions and the judges and governors executed them. 'Umar also made the adoption that land obtained in war was a ghanima owned by the Bait ul Mal (House of Funds), wherein the original owners would retain possession and not distribute the land to the Muslim soldiers or the Muslims. The governors and judges followed him in this adoption and enacted the aHkam he had adopted. Accordingly, the consensus of the Companions (ijma'a as-sahabah) confirms that the Imam has the authority to adopt certain rules and order that they be executed and the Muslims must obey him, even if their ijtihad differs from it. Among the well known shar’aiah principles are:

苏丹有权颁布与实际问题数量相当的法令。

"The Sultan has the right to adopt decrees as numerous as the actual problems";.

伊玛目的裁决平息了分歧；并且。

"The Imam's decre e resolves the discord"; and.

伊玛目的命令在公开与私下里都得到执行。

"The Imam's command is executed openly and covertly".

此后，哈里发们采纳了特定的律例（Ahkam）。例如，哈伦·拉希德（Haroon ar-Rasheed）在经济事务方面采用了《土地税之书》（Kitab al-Kharaj），并强制所有民众执行其中所包含的律例。

Henceforth, the Khulafa'a adopted specific AHkam. Haroon ar-Rasheed, for example, adopted the book Kitab al-Kharaj in the economic affairs, and he obliged all the people to execute the AHkam included within it.