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
Hadith of the Quran and Sunnah single manner. The hadith also refutes the shi'a tradition that the wives of the Prophet are not part of ahlul bayt. Because the truth of the matter is that Zaid clearly says, "His wives are the members of his family...". It is true that he mentions that the hadith is pertaining to Ali, Aqil, and Jafar, and all their offsprings; but, as is the well-known position in the sunni tradition, a companion or anyone other than the prophet can not make official any ruling or opinion. Zaid did not tell why he believes the hadith is pertaining only to Ali,