The Method of Shi'ism in Authenticating the Hadith

Shi'ism, in addition to seeking to authenticate the chain of
transmission of hadith, considers the correlation of the text of the
hadith with the Qur'an as a necessary condition for its validity. In
Shi'ite sources there are many hadith of the Prophet and the Imams
with authentic chains of transmission which themselves assert that a
hadith contrary to the Qur'an has no value. Only that hadith can be
considered valid which isin agreement with the Qur'an.
Basing itself on these hadiths, Shi'ism does not act upon those
hadiths which are contrary to thetext of the Qur'an. As for hadiths
whose agreement or disagreement cannot be established according to
instructions received from the Imams they are passed by in silence
without being accepted or rejected.
Needless to say there are also within Shi'ism those who, like a group
amongthe Sunnis act on any hadith whatsoever whichthey happen to find
in different traditional sources.
The Method of Shi'ism in Following the Hadith
A hadith heard directly from the mouth of the Prophet or one of the
Imams is accepted as is the Qur'an. As for hadiths received through
intermediaries, the majority of Shi'ites act upon them if their chain
of transmission is established at every step or if there exists
definite proof concerning their truth, and, if they are concerned with
principles of doctrine which require knowledge and certainty,according
to the text of the Qur'an. Other than these two kinds of hadith, no
other hadith has any validity concerning principles of doctrine, the
invalid hadith being called "tradition with a sincere transmitter"
(khabar wahid). However, in establish in the injunctions of the
Shari'ah, because of reasons that have been given, Shi'ites act also
on a tradition which is generally accepted as reliable. Therefore, it
can be said that for Shi'ism a certain and definitely established
hadith is absolutely binding and must be followed, while a hadith
which is not absolutely established but which is generally considered
as reliable is utilized only in the elaboration of the in junctions of
the Shari'ah.