A specific ijāzah may identify a named recipient and a named work, such as “I authorize Zayd to narrate this book.” Both parties and the content are clear. By contrast, general ijāzah—“I authorize all Muslims,” for example—may address an extremely broad and impersonal class.
Classical and later scholars disputed the permissibility and usefulness of broad authorizations. Membership in a general class is not equivalent in evidentiary strength to a direct audition or a tightly specified personal permission.
Example: “I authorize my pupil Ḥamzah for this named work” differs from “I authorize everyone in the city for all my books” in specificity, control, and traceability. The legal debate about validity is distinct from comparative evidentiary value.