Hadith as Sunna, but it is not necessary that a Sunna would have a supporting hadith sanctioning it. Some sources (Khaled Abou El Fadl) limit hadith to verbal reports, with the deeds of Muhammad and reports about his companions being part of the "Sunnah", but not hadith. Joseph Schacht quotes a Hadith by Muhammad that is used "to justify reference" in Islamic law to companions of Muhammad as religious authorities — "My companions are like lodestars." According to Schacht, (and other scholars) in the very first generations after the death of Muhammad, use of hadith from "Sahabah" ("companions" of Muhammad) and
Introduction to the Science of Hadith chapters, each covering a hadith related issue. The first 33 chapters describe the various technical terms of hadith terminology which describe the conditions of a hadith's authenticity, or acceptability as a basis for Islamic jurisprudence. The following chapters relate to the "isnād", or chain of narration. Next are a series of chapters pertaining to the etiquette to be observed by hadith scholars and manners of transcription. The last chapters describe various issues relating to the narrators of hadith including naming conventions. Ibn al-Ṣalāḥ began the "Introduction" as a series of lectures he dictated to his students in Damascus ending in