Musannaf Ibn Abi Shaybah

Hazrat Abdul Malik says that Hazrat Sha’bi was asked about a man who said to another man: “O adulterer!” and he knows that he has committed adultery, so will the punishment of false accusation (qadhf) be imposed on him? He replied: Yes, indeed Allah, the Lord of Honor, has said: “Then if they do not bring four witnesses...”