Mu'jam Kabir Tabarani 5658 — a man of the Ansar came to the Messenger

Sayyiduna Sahl bin Sa'd (may Allah be pleased with him) said that a man of the Ansar came to the Messenger of Allah (peace and blessings be upon him) and said: "O Messenger of Allah! What do you think of a man who finds a (strange) man with his wife: should he kill him?" Thereupon Allah, the Mighty and Majestic, revealed concerning him the verses about li'an (mutual imprecation) that are mentioned in the Qur'an. He (peace and blessings be upon him) said: "Judgement has been given concerning you and your wife." The narrator said: So the two of them performed li'an, and I was a witness to it. Then he separated from her right there in the presence of the Messenger of Allah (peace and blessings be upon him), and after that it became the practice that the couple who perform li'an are separated. She was pregnant, and he denied her pregnancy, so the child used to be attributed to his mother. Then the practice in inheritance also became established that the son inherits from her, and she inherits from him the share that Allah has prescribed for her.