What is the meaning of the narrators' saying about hadiths: "It is not authentic" and "It is established"? And what is the meaning of Ibn Kathir's saying about a hadith: "There is strangeness in it" or "It is remarkably strange"? And does "strange" mean that it was narrated by only one narrator? And is strangeness found in the text (matn) or in the chain of transmission (sanad)? And if it is in the text, what does that mean?

The hadith that is not authentic is one that has lost one or more of the conditions of authenticity. It does not necessarily mean that because it is not authentic, it is fabricated. As for the established hadith, it is one that has met the conditions of acceptance, and it includes the authentic (sahih) and the good (hasan). The oddity (gharaba) in a hadith may be in the text (matn) or the chain of transmission (sanad), and it means that a single narrator is unique in narrating it, or in adding to it. The narrator may be trustworthy or weak. Ibn Kathir is not known to have used the expression "strange and wondrous oddity" (gharaba ajiba) in his tafsir; rather, he used "severe oddity" (gharaba shadida) and "strange and wondrous narration" (athar gharib ajib).