Ikrimah narrates from Abdullah bin Abbas (may Allah be pleased with them both) that when Hilal bin Umayyah (may Allah be pleased with him) accused his wife, Hilal bin Umayyah (may Allah be pleased with him) was told: The Messenger of Allah (peace and blessings be upon him) will give you 80 lashes. He said: Allah, the Lord of Might, is more just than to have me given 80 lashes. Allah knows that I saw until I was certain, and heard until it was clear. By Allah! He will not have me lashed. Then the verses of li'an were revealed, and the Messenger of Allah (peace and blessings be upon him) called both husband and wife when the verse was revealed. He (peace and blessings be upon him) said: "Allah knows that one of you is lying; so is one of you ready to repent?" Hilal said: I am truthful. He (peace and blessings be upon him) said: "Swear by Allah, besides whom there is no god, that 'I am truthful'. Swear this four times, (then say:) 'If I am a liar, then the curse of Allah be upon me.'" He (peace and blessings be upon him) said: "Stop him at the fifth oath, for it makes (the punishment) binding." Then she swore four times, saying: By the One besides whom there is no god, he is of the liars; and if this man is truthful, then the wrath of Allah be upon me. He (peace and blessings be upon him) said: "Stop this woman at the fifth oath, for it makes the punishment binding." She hesitated and was about to confess, then said: I will not disgrace my people. The Messenger of Allah (peace and blessings be upon him) said: "If this woman gives birth to a child with dark (kohl-like) eyes, heavy buttocks, a thick back and very thick shins, it is Sharik bin Sahma's; and if she gives birth to one with a yellowish complexion and straight hair, it is Hilal bin Umayyah's." She gave birth to a child with the features of the adulterer. Ayyub and Muhammad bin Sirin (may Allah have mercy on them both) say that the man whom Hilal bin Umayyah (may Allah be pleased with him) accused concerning his wife was the brother of al-Bara bin Malik (may Allah be pleased with him); his mother was black, and Sharik used to stay in Hilal's house. The Shaykh has called li'an an oath.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب اللعان / 15294