The prophetic traditions constitute the second root of the law. They are understood to be subordinate to the Quran. There are several reasons for this.
First, prophetic traditions are reports by different narrators. They were compiled two hundred years after the demise of the prophet.
Second, the majority of the traditions (ahadith) are paraphrases of the words of the prophet. Just ten traditions are known to be verbatim, literally the words of the prophet.
Third, there is a lack of consensus about whether the prophet permitted the compilations of his sayings. There is evidence, ironically in the compilations themselves, that at least initially he forbade it, for fear that the words the Quran might be mixed up with his words. There appears to be a dearth of evidence that he relaxed the prohibition.
Fourth, the vast majority of the traditions are solitary, meaning that they are supported by just a single chain of narration. A few jurists feel that single-chain narrations should not be used as a root of the law. According to them, only traditions with multiple lines of narration should be used as roots of the law.
The reason for this was that the reliability of traditions with at least four separate chains of narration was deemed to be higher than that of solitary traditions.
Fifth, different denominations appear to have different compilations of traditions.
Sixth, there was widespread forgery of traditions taking place at the time. Many traditions were fabricated to support either one or another of several competing parties.
Seventh, the process of verifying the authenticity of the narrations did not pay enough attention to the meaning (matn) of the tradition, and was excessively concerned with the reliability of the narrators.
Eighth, the traditions appear to have left out statements about the intellect and justice, thereby appearing to be excessively focused on formalities.
Ninth, a few traditions appear to depart from the teaching of the Quran on various subjects, such as apostasy.
Jurists generally agree that if a tradition is authentic and agrees with the Quran, relying on it should be acceptable.
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