Purpose of ‘Ilm al-Hadith...
Purpose of ‘Ilm al-Hadith: Ibn Khaldun, in his Muqaddimah, under chapter `ulum al-hadith" p.417 writes: One of the sciences of hadith being to examine the asanid and recognizing which traditions having required conditions to be followed and adopted. Because we should act according to the akhbar of the Messenger of Allah that are thought to be true, exerting our effort on the way through which we reached to that surmise, which lies in knowing the narrators with reliability and exactitude... etc.
In his exposition of Muslim's sermon, al-Nawawi says: The purpose of ‘ilm al-hadith 504 is to establish the meanings of the texts and science of isnad and accountability. Cause (‘illah) is a meaning in the hadith that is concealed and resulting in weakening the hadith though it on the surface is free from it. And ‘illah may be some time in the text, and another time in the isnad (ascription).
The purpose of this science is neither merely hearing nor making to hear nor writing, 505 but rather it is paying attention to it, frequenting to men of knowledge and reading the books of investigators and researchers on it. 506 Ascription and Text of Hadith: Lexical meaning of sanad is that on which you rest or recline, like a wall or alike, but among the men of hadith it means the way (tariq) of the hadith text.
It has been called sanad due to dependence of the memorizers upon it for recognizing whether the hadith being correct or fabricated. For tariq the word wajh may be used, when saying. This hadith cannot be recognized but only through this wajh. And matn lexically means the back and whatever is hardened and high of the land, that then was commonly used to refer to the end of ascription (sanad).
The example for this is the statement of Yahya: Malik reported from Nafi', from Abd Allah ibn Umar that the Messenger of Allah said: None of you should sell or make a deal so as to make others lose it. The sanad of the hadith being the narrators and matn (text) of the hadith being "None of you should sell...
etc." From Whom Hadith Should be Taken: Ulama’ of hadith unanimously concur that hadith is not to be considered authentic but only when its narrators having two traits; adalah (reliability) and exactitude, with adalah being the greatest cornerstone for narration.