Hadith root of why there is no single "fiqh" system, but rather a collection of parallel systems within Islam. Much of early Islamic history available today is also based on the hadith, although it has been challenged for its lack of basis in primary source material and the internal contradictions of the secondary material available. Hadith may be "hadith qudsi" (sacred hadith) — which some Muslims regard as the words of God (Arabic: Allah) — or "hadith sharif" (noble hadith), which are Muhammad's own utterances. According to as-Sayyid ash-Sharif al-Jurjani, the hadith qudsi differ from the Quran in that the former
Introduction to the Science of Hadith clarify that term and not necessarily establish it. He also distinguished his book by responding to the positions of other scholars in a detailed manner. Ibn al-Ṣalāḥ mentioned in his introduction to the "Introduction" 65 chapters, each specific to a particular type or term of hadith terminology before saying that an even larger number was conceivable. He began by discussing "ṣaḥīḥ" (authentic) as the first category, and then "ḥasan" (good) as the second, "ḍa`īf" (weak) the third, "musnad" (supported) the fourth and so on. Ibn Jamāʻah, in his abridgement, divided these terms into four different categories according to subject (and