Sunan Abi Dawud

Sunan Abi Dawud is Abu Dawud al-Sijistani's ninth century hadith collection, one of the six books, al-kutub al-sittah, recognized within Sunni Islam as authoritative compilations of the Prophet Muhammad's sayings and actions. Abu Dawud is reported to have gathered some five hundred thousand hadith and selected around 4,800 for inclusion, organizing them by legal topic and noting, in many cases, his own judgment of a hadith's reliability rather than presenting the collection as uniformly sound. Its strength is exactly that transparency, a compiler working within an established science of hadith criticism and saying so, plus its enduring status as one of the six canonical books read for over a millennium. Its limit is that the collection includes hadith of varying strength that Abu Dawud graded honestly rather than filtering out, so a claim resting on a specific hadith from this collection needs its individual grading, not the collection's canonical status alone, since canonical does not mean every included report carries the same authority.