Sahl bin Saad reported,

A man from the Ansar came to the Messenger of Allah ﷺ and asked, "Messenger of Allah, what is your view about a man who finds another man with his wife? Should he kill him, or what should he do?" Then Allah revealed concerning his case what is mentioned in the Quran about the Mutalaineen.The Prophet ﷺ said, "Allah has issued His ruling concerning you and your wife."So the two of them performed the mutual imprecation in the mosque while I was present. When they had finished, the man said, "I would have lied against her, Messenger of Allah, if I kept her." So he divorced her three times before the Messenger of Allah ﷺ could instruct him to do so, when they had finished the mutual imprecation. He thus separated from her in the presence of the Prophet ﷺ, who said, "That is the separation between every couple who perform mutual imprecation."Ibn Jurayj reported from Ibn Shihab, from Sahl bin Saad al-Saidi, in this same hadith, that the Prophet ﷺ said, "If she gives birth to a child who is red and short, resembling a wahrah lizard, then I see that she has told the truth and he has lied against her. But if she gives birth to a child who is dark, with prominent eyes and large buttocks, then I see that he has spoken the truth against her."She gave birth to the child bearing the unfavorable description.

عن سهل بن سعد أخي بني ساعدة

أن رجلا من الأنصار جاء إلى رسول الله ﷺ فقال: يا رسول الله، أرأيت رجلا وجد مع امرأته رجلا أيقتله أم كيف يفعل؟ فأنزل الله في شأنه ما ذكر في القرآن من أمر المتلاعنين فقال النبي ﷺ: قد قضى الله فيك وفي امرأتك قال: فتلاعنا في المسجد وأنا شاهد. فلما فرغا قال: كذبت عليها يا رسول الله إن أمسكتها، فطلقها ثلاثا قبل أن يأمره رسول الله ﷺ حين فرغا من التلاعن، ففارقها عند النبي ﷺ فقال: ذاك تفريق بين كل متلاعنين. قال ابن جريج، عن ابن شهاب، عن سهل بن سعد الساعدي في هذا الحديث إن النبي ﷺ قال: إن جاءت به أحمر قصيرا، كأنه وحرة، فلا أراها إلا قد صدقت، وكذب عليها. وإن جاءت به أسود أعين، ذا أليتين فلا أراه إلا قد صدق عليها فجاءت به على المكروه من ذلك.