Taḥammul is to receive the hadith from someone else, whereas adāʾ is to convey it to others. Delivery employs several formulae, among them:

1. ḥaddathanī ("he narrated to me"): used when the teacher reads the text to the student.
2. akhbaranī ("he informed me"): used either when the teacher reads to the student or when the student reads to the teacher.
3. akhbaranī ijāzah, or ajāza lī ("he informed me by ijāzah" or "he granted me permission"): used when the narration rests on an ijāzah without any reading. An ijāzah is the teacher’s authorization for the student to transmit on his authority what the teacher himself relates, even though no reading has taken place.
4. al-ʿanʿanah: reporting a hadith with the word ʿan ("from"). Its chain is presumed connected unless the narrator is known for tadlīs (concealing an intermediary); in that case it is not deemed connected unless he explicitly says, "he narrated to me."

There are many other branches in the science of hadith methodology that examine the reports and their transmitters, but what we have touched upon here is sufficient, if Allah wills.