Musannaf Ibn Abi Shaybah

Hazrat Qatadah narrates that it is reported from Hazrat Saeed bin Musayyib regarding a man who said to his wife: "I saw you committing adultery before you came to me." Hazrat Saeed said: The punishment of qazf (false accusation of adultery) will be imposed on him and there will be no li'an (mutual cursing). And Hasan Basri said: Neither the punishment of qazf will be imposed nor li'an will take place, because he said this to the woman at a time when she was already with him.