Hadith remembers God unceasingly. (Al-Ahzab 33: 21) The hadith literature is based on spoken reports in circulation after the death of Muhammad. Unlike the Qur'an, ahadith were not promptly written down during Muhammad's life or immediately after his death. Hadith were evaluated and gathered into large collections during the 8th and 9th centuries, generations after the death of Muhammad, after the end of the era of the "rightful" Rashidun Caliphate, over from where Muhammad lived. "Many thousands of times" more numerous than Quranic verse, ahadith have been described as resembling layers surrounding the “core” of the Islamic belief (the Quran). Well-known,
Criticism of Hadith these not just inspirational or informational but laws "sacrosanct or immutable Shari'ah" to be enforced, and because to others (especially modernist and liberal Muslims) the laws thus developed are "contrary to the intent and spirit of the Qur'an and Islam's fundamental commitment to justice and fairness", the "problem of the authenticity of the Sunnah" or hadith has become an issue for those (especially modernist and liberal Muslims) who believe there is a conflict between the "intent and spirit of the Qur'an" and "centuries-old" ahadith-based jurisprudence. According to M.O. Farooq, despite the widespread belief that sahih hadith are authentic hadith and