Isnads

Hadith studies (Arabic: علم الحديث‎‎ ʻilm al-ḥadīth "knowledge of hadith" or science of hadith) are a number of religious disciplines used in the study and evaluation of the Islamic hadith (the collections of the reports of what the Islamic prophet Muhammad said verbatim on any matter) by Muslim scholars. It has been described by one hadith specialist, Jalal al-Din al-Suyuti, as the science of the principles by which the conditions of both the sanad, the chain of narration, and the matn, the text of the hadith, are known. This science is concerned with the sanad and the matn with its objective being distinguishing the sahih, authentic, from other than it. Ibn Hajar al-Asqalani said the preferred definition is: knowledge of the principles by which the condition of the narrator and the narrated are determined.

A common historical method in Islam, hadith studies consist of a careful examination of the isnad, or chain of transmission accompanying each hadith.The isnad is carefully scrutinized to see if the chain is possible (for example, making sure that all transmitters and transmittees were known to be alive and living in the same area at the time of transmission) and if the transmitters are reliable. The scholars reject as unreliable people reported to have lied (at any point), as well as people reputed to be heedless (and thus likely to misunderstand the saying).

The stature of hadith studies reflects the centrality of hadith to other religious disciplines. “The science of hadith is from the best of the virtuous sciences as well as the most beneficial of the various disciplines,” said Uthman ibn Abd al-Rahman al-Shahrazuri, commonly known as Ibn al-Salah, in the introduction to his widely influential Introduction to the Science of Hadith. “It is preferred by the noble from amongst men and is tended to by those scholars concerned with verifying the correct from the incorrect and those of complete scholarship; only those who are debased and lowly dislike it. It is the science most pervasive in respect to the other sciences in their various branches, in particular to jurisprudence being the most important of them.”

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