Sahih al-Bukhari Book 68, Hadith 60
I asked Ibn `Umar, "(What is the verdict if) a man accuses his wife of illegal sexual intercourse?" Ibn
`Umar said, "The Prophet (ﷺ) separated (by divorce) the couple of Bani Al-Ajlan, and said, (to them),
'Allah knows that one of you two is a liar; so will one of you repent?' But both of them refused. He
again said, 'Allah knows that one of you two is a liar; so will one of you repent?' But both of them
refused. So he separated them by divorce." (Aiyub, a sub-narrator said: `Amr bin Dinar said to me,
"There is something else in this Hadith which you have not mentioned. It goes thus: The man said,
'What about my money (i.e. the Mahr that I have given to my wife)?' It was said, 'You have no right to
restore any money, for if you have spoken the truth (as regards the accusation), you have also
consummated your marriage with her; and if you have told a lie, you are less rightful to have your
money back.' ")
Ibn `Abbas; said, "Once Lian was mentioned before the Prophet (ﷺ) whereupon `Asim bin Adi said something and went away. Then a man from his tribe came to him, complaining that he had found a man with his wife. `Asim said, 'I have not been put to task except for my statement (about Lian).' `Asim took the man to the Prophet (ﷺ) and the man told him of the state in which he had found his wife. The man was pale, thin, and of lank hair, while the other man whom he claimed he had seen with his wife, was brown, fat and had much flesh on his calves. The Prophet (ﷺ) invoked, saying, 'O Allah! Reveal the truth.' So that lady delivered a child resembling the man whom her husband had mentioned he had found her with. The Prophet (ﷺ) then made them carry out Lian." Then a man from that gathering asked Ibn `Abbas, "Was she the same lady regarding which the Prophet (ﷺ) had said, 'If I were to stone to death someone without witness, I would have stoned this lady'?" Ibn `Abbas said, "No, that was another lady who, though being a Muslim, used to arouse suspicion by her outright misbehavior. "
I asked Ibn `Umar about those who were involved in a case of Lien. He said, "The Prophet (ﷺ) said to those who were involved in a case of Lien, 'Your accounts are with Allah. One of you two is a liar, and you (the husband) have no right over her (she is divorced)." The man said, 'What about my property (Mahr) ?' The Prophet (ﷺ) said, 'You have no right to get back your property. If you have told the truth about her then your property was for the consummation of your marriage with her; and if you told a lie about her, then you are less rightful to get your property back.' " Sufyan, a sub-narrator said: I learned the Hadith from `Amr. Narrated Aiyub: I heard Sa`id bin Jubair saying, "I asked Ibn `Umar, 'If a man (accuses his wife for an illegal sexual intercourse and) carries out the process of Lian (what will happen)?' Ibn `Umar set two of his fingers apart. (Sufyan set his index finger and middle finger apart.) Ibn `Umar said, 'The Prophet (ﷺ) separated the couple of Bani Al-Ajlan by divorce and said thrice, "Allah knows that one of you two is a liar; so will one of you repent (to Allah)?' "