In ijāzah, a teacher authorizes a pupil to transmit a designated narration, book, or collection. It is permission to transmit, not necessarily evidence that a listening or reading session occurred. Permission may be oral or written, specific or broad, and different forms vary in their probative value.
Example: A teacher says:
«أَجَزْتُ لَكَ رِوَايَةَ هَذَا الْكِتَابِ»
I authorize you to narrate this book.
The student has not thereby heard the entire text from the teacher or read it aloud to him.
Scholarly conventions about the validity and wording of ijāzah changed over time. Explicitly indicating “by ijāzah” can preserve the real means of acquisition when an unqualified direct-hearing formula would mislead.