Musnad Abu Ya'la al-Mawsili 154:26

Mujahid ibn Musa al-Khatli narrated to us, Ishaq ibn Yusuf narrated to us, Abd al-Malik narrated to us, from Sa’id ibn Jubayr, who said: I was asked about the two who perform *li’an* (mutual cursing) during the time of Mus’ab: "Is there a separation between them?" I did not know what to say. So, I went early to the house of Abdullah ibn Umar and asked for permission to see him. They said, "He is sleeping." He heard my voice and said, "Ibn Jubayr, let him in." I entered upon him, and he said, "Nothing brought you at this hour except a need." He was sitting on the saddlecloth of his mount, leaning on a pillow stuffed with palm fiber or *silt* (a type of grass). I said to him, "O Abu Abd al-Rahman, is there a separation between the two who perform *li’an*?" He said, "Subhan Allah! Yes. The first person to ask about this was so-and-so, son of so-and-so. He came to the Prophet, peace and blessings of Allah be upon him, and said, 'O Messenger of Allah, what do you think if one of us sees his wife committing an indecency? How should he act? If he speaks, he speaks of a grave matter, and if he remains silent, he remains silent upon the like of that.' The Prophet, peace and blessings of Allah be upon him, did not answer him. Then, after a while, he came to the Prophet, peace and blessings of Allah be upon him, and said, 'O Messenger of Allah, that which I asked you about, I have been afflicted with it.' Then Allah revealed the verses in Surah al-Nur: 'And those who accuse their wives...' until the end of the verse. He said: So he called for the man and recited them to him, exhorted him, reminded him, and informed him that the punishment of the world is lighter than the punishment of the Hereafter. He said, 'By the One who sent you with the truth, I have not lied about her.' He said: Then the Prophet, peace and blessings of Allah be upon him, called for the woman and recited them to her, exhorted her, reminded her, and informed her that the punishment of the world is lighter than the punishment of the Hereafter. She said, 'By the One who sent you with the truth, he has not told the truth, and he has lied.' He said: Then the Prophet, peace and blessings of Allah be upon him, began with the man, and he testified four times by Allah that he was indeed among the truthful, and the fifth [time] that the curse of Allah be upon him if he were among the liars. Then the Prophet, peace and blessings of Allah be upon him, called for the woman, and she testified four times by Allah that he was indeed among the liars, and the fifth [time] that the wrath of Allah be upon her if he were among the truthful. Then the Prophet, peace and blessings of Allah be upon him, separated them."