What is the definition of an Ahad Hadith, and approximately how many of them are there in the authentic collections (kutub al-Sihah)? Is its authenticity presumptive (dhanni al-thubut)? Is it acted upon in matters of aqidah (creed), fiqh (jurisprudence), stories of the prophets, and the Sirah (Prophet's biography)? Who are the scholars who accepted it and who rejected it, and what is the evidence for each group? Is it permissible to reject it if it contradicts the general rules and fundamental principles of Sharia?

The correct view is that khabar al-ahad (a solitary narration) is acted upon in matters of creed (aqidah), jurisprudence (fiqh), stories, and biographies. The vast majority of scholars, both early and late, have held that khabar al-ahad is acceptable and constitutes a proof in all religious matters. Ibn Abi Dawud, some of the Mu'tazilah, the Qadariyah, the Zahiriyah, and the Rafidah dissented from this view. Scholars differed when a solitary narration contradicted the general principles of Sharia, as to which should be given precedence. Abu Hanifa held that it is not permissible to act upon it, while Shafi'i permitted it, and Malik hesitated on the matter.