安拉以伊斯兰教法（Shari'ah）的全部内容向负有法律责任的人（mukallafīn）发出训谕，包括其根基与枝节，即信仰以及与行为相关的律例。然而，乌苏勒·菲格（Usūl al-Fiqh）这门学科并不关注根基（信仰），而是关注枝节（与行为相关的法律裁定）。此外，它所关注的是与行为相关的法律裁定，其角度在于裁定所依据的基础，而非裁定所包含的各种规则和具体问题。因此，在研习法律依据的知识时，有必要领会法律裁定（hukm shar'i）的实质。

Allah addresses the legally responsible persons [mukallafīn] with the entirety of the Islamic Shari’ah, comprising both its foundations and branches, that is, the beliefs and the rules related to actions. However the science of Usūl al-Fiqh is not concerned with the foundations (beliefs). Rather it is concerned with the branches (legal rulings related to actions). Further it is concerned with the legal rulings related to actions from the perspective of the bases upon which the rulings are built, not from the perspective of the various rules and issues a rulings contains. Hence it is necessary to appreciate the reality of the legal ruling [hukm shar’i] when studying the knowledge of the legal evidences.

学者们在法源学（usūl）中将法律裁定（hukm shar‘ī）定义为：立法者与仆人之行为相关的命令，其形式或为强制（iqtidā’），或为选择（takhyīr），或为设定（wad’）。立法者即安拉，至高无上，因此“立法者的命令”即安拉的命令。此外，尽管安拉的命令指引听者趋向某些规则与原则，但命令本身即是原义，而非其所指向的内容。因此，词语与复合结构所表示的意义本身就是命令。 之所以用“立法者的命令”而非“安拉的命令”，是为了涵盖圣训（Sunnah）与圣门弟子的一致意见（Ijma’ al-Sahabah），因为二者同样表明安拉的命令。若用“安拉的命令”，可能会造成只指《古兰经》的错误印象；然而圣训同样是启示，因此也是立法者的命令；圣门弟子的一致意见则揭示了来自圣训的证据，故它同样是立法者的命令。 之所以用仆人（‘ibād）的行为，而非“负有义务者”（mukallafīn），是为了涵盖与儿童和精神失常者相关的裁定，例如他们的财产上应缴纳的天课（zakāh）。

The scholars of usūl have defined the legal ruling as ‘the address of the legislator related to the actions of the servants in terms of compulsion [iqtidā’], choice [takhyīr], or declaration [wad’]. The legislator is Allah, the Exalted, and hence the ‘address of the legislator’ means the address of Allah. Further, although the address of Allah directs the listener towards certain rules and principles, the address is the original meaning itself not what it directs towards. Thus the very meaning which the words and compounds denote is the address. The reason for using ‘the address of the legislator’ instead of ‘the address of Allah’ is to include the Sunnah and the Ijma’ al-Sahabah, both of which also signify the address of Allah. The use of ‘the address of Allah’ may give the wrong impression that the Qur’an alone is intended; yet the Sunnah too is revelation and as such is the address of the legislator, and the Ijma’ al-Sahabah reveals an evidence from the Sunnah so it too is the address of the legislator. The reason for using actions of the ‘servants’, instead of ‘mukallifīn’ is so as to include the rulings related to the child and the insane like the zakat due on their wealth.

"法律裁定与要求（iqtidā’）相关"的含义，在于它与一种"要求"（talab）相关，因为iqtidā’一词的含义即是talab。要求分为两种：要求行为，以及要求避免。若要求行为是确定性的（jāzim），则表示义务（ījāb，fard）；若是非确定性的，则表示推荐（mandūb，sunnah，nāfilah）。若要求避免是确定性的，则表示禁止（tahrīm，hadhr）；若是非确定性的，则表示厌恶（karahah）。至于选择（takhyīr），则表示许可。 至于宣告性的指令（wad’），或与仆人行为相关的宣告性指令，则是将某事物设定为原因（sabab）或阻碍因素（mani’）等，例如日落是礼拜出现的必然因素，因而成为礼拜的原因（sabab）；又如不洁是礼拜的阻碍因素。因此，这些事物虽然是对裁定的标志（‘alamah），它们本身也是裁定。真主使太阳离开天顶（zawāl）成为晌礼出现的标志，使不洁的存在成为礼拜无效的标志。zawāl具有必然性，其含义只在于它是一种要求进行礼拜的指令；不洁具有使礼拜无效的作用，其含义也只在于它是一种要求避免不洁的指令。因此，这些事物就其实质而言，是来自立法者（Ash-Shaari'）的指令。

The meaning of the legal ruling being related to compulsion [iqtidā’] is its being related to a request [talab], because the meaning of the word iqtidā’ is talab. The request is of two types: the request to act, and the request to abstain. If the request to act is decisive [jāzim] then it denotes the obligation [ījāb, fard], and if it is non-decisive then it denotes the recommendation [mandūb, sunnah, nāfilah]. If the request to abstain is decisive then it denotes the prohibition [tahrīm, hadhr], and if it is non-decisive then it denotes the reprehensibility [karahah]. As for choice [takhyīr] it denotes the permissibility. As for the address of declaration [wad’], or the address related to the action of the servants in terms of declaration, then it is the making of a thing a cause [sabab] or preventative factor [mani’] etc. like the sunset being the necessitating factor for the presence of the prayer, and thereby being the cause [sabab] of prayer, and like the impurity being a preventative factor for prayer. Hence these things, whilst they are signs [‘alamah] for the rulings, they are also rulings in their own right. Allah has made the moving of the Sun from its zenith [zawāl] the sign for the presence of Dhuhr, and the presence of impurity a sign for the invalidity of prayer. There is no meaning to the zawāl being necessitating except its being a request to perform the prayer, nor is there a meaning to the impurity invalidating except its being a request to abstain from impurity. As such these things in their reality are an address from the Legislator.

因此,将“立法者关于仆人行为的训令”定义为“沙里发的判断(hukm shar'i)”,既全面又排他[jāmi' māni']。由于其涉及强制或选择的关系,它涵盖了五种裁决:wājib(必行)、mandūb(推荐)、harām(禁止)、makrūh(厌恶)、mubāh(允许);由于其涉及宣告,它涵盖了sabab(原因)、shart(条件)、māni'(障碍)、ṣaḥīḥ(有效)、bāṭil(无效)、fāsid(无效/瑕疵)、rukhṣah(宽免)和'azīmah(常道)。基于此定义,立法者的训令分为两类:责任性训令[khitāb al-taklīf]和宣告性训令[khitāb al-waḍ']。

Hence the definition of the hukm shar’i as ‘the address of the legislator related to the actions of the servants’ is both comprehensive and exclusive [jāmi mani’]. With its reference to the relation to compulsion or choice it covers the five rulings: wājib, mandub, harām, makruh, mubah, and by its reference to the declaration it covers the sabab, shart, mani’, sahih, batil, fāsid, rukhsah and azimah. On the basis of this definition the address of the Legislator is of two types: the address of responsibility [khitab al taklīf] and the address of declaration [khitab al-wad’].