I said to Ibn Umar, "What about a man who accuses his wife of adultery?"He replied, "The Messenger of Allah ﷺ separated the two siblings of Banu Ajlan and said, 'Allah knows that one of you is lying, so will either of you repent?' He repeated this three times, but they both refused, so he separated them."
حدثنا أحمد بن محمد بن حنبل حدثنا إسمعيل حدثنا أيوب
قلت لابن عمر رجل قذف امرأته قال فرق رسول الله ﷺ بين أخوي بني العجلان وقال الله يعلم أن أحدكما كاذب فهل منكما تائب يرددها ثلاث مرات فأبيا ففرق بينهما
Bukhari narrated it in Kitab al-Talaq, Bab Sadaq al-Mulaana, no. 5311, from the hadith of Ismail bin Ulaya, and Muslim narrated it in Kitab al-Lian, no. 6/1493, from the hadith of Ayub Sakhtiyani, with the same chain.