Since the authenticity of a hadith was absolutely crucial, the authentication of hadith developed into an exacting discipline. At its core, it consisted of nailing down the chain of transmission and testing the veracity of every link. A hadith was only as good as the people who transmitted it. The chain of transmission had to extend to someone who knew the Prophet personally. Only then could a purported hadith be taken seriously. Ideally, it would trace to one of Mohammed’s close companions, and the closer the companion the more sound the hadith. In addition, every person who transmitted it
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