Since there are some incorrect hadiths among hadith collections, religious scholars, based on rational and religious criteria, have established two sciences of rijal and diraya for characterization of various kinds of hadith. In the field of rijal, they consider the chain of narrators as well as individual narrators to evaluate the validity of hadiths; then they classified hadiths as follows: sahih, muwaththaq, hasan (praised hadith), da'if (weak hadith).
Definition and Stipulations
- Sunnis and some of Shi'a scholars added the stipulations of lack of "shuzuz" or "illa" (weakness or sickness) to the definition. What is meant by shuzuz is the fact that the hadith is contradicted with mashhur hadith (generally accepted hadith); and what is meant by "illa" is a hidden defect which entails to the weakness of the hadith; for example it turns out that there is an omission in the chain of an apparently authentic hadith.
- Some scholars such as al-Bukhari in his book, Sahih, have stipulated the narrator's meeting with whom the hadith is narrated form. But, other Sunni scholars such as Muslim b. Hajjaj and most Shi'a scholars have denied this term.
- Al-Shafi'i, al-Sakhawi and some other Sunni scholars have denied denominational ascription as a criterion for acceptance of a hadith; they would accept the trustworthy narrators of hadiths regardless of their denominations. al-Khatib al-Baghdadi narrates from Ali b. al-Madini (one of Sunnis great scholars of hadith) that he would say, "if we reject Kufan hadiths just due to their belief in Shi'ism, all the hadith collections will be disappeared."
Early Scholars' View on Sahih Hadith
The definition of sahih hadith by early scholars is different with it by recent ones. From early scholars' point of view, a sahih hadith is a narration whose issuance from Imams (a) would be proved from any possible way. They simply classified hadiths to acceptable and unacceptable. The new classification of hadith to sahih, muwaththaq, hasan, and da'if was proposed at the time of al-Allama al-Hilli or his teacher al-Sayyid b. Tawus. The first three kinds, i.e. sahih, muwaththaq and hasan, were counted as acceptable before early scholars.
Classification of Sahih Hadith from Shi'a Point of View
Sahih's degrees are as follows:
1- A'la (highest): All the narrators are trustworthy weather we know the fact or we accept it from two just witnesses.
2- Awsat (middle): All the narrators or one of them are trustworthy just based on a report of one just witness.
3- Adna (lowest): The trustworthiness of the transmitters is based on jurisprudential conjecture.
Classification of Sahih Hadith from Sunni Point of View
- A hadith which, besides the stipulations of authenticity, are mentioned in both Sahih al-Bukhari and Sahih Muslim and it is usually called as "Muttafiq Alayh" (agreed upon) hadith or Sahih A'la.
- A hadith which is just mentioned in Sahih al-Bukhari.
- A hadith which is just mentioned in Sahih Muslim.
- A hadith which has the stipulations determined by Muslim and al-Bukhari but it is not mentioned in their books.
- The material for this article is mainly taken form حدیث صحیح in Farsi WikiShia.