Sahih al-Bukhari 4914
Sahih al-Bukhari · Book 65: Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh)) · "And (remember) when the Prophet pbuh disclosed a matter in confidence to one of his wives (Ḥafsa) (up to) ... The All-Aware." (V.66:3)
Narrated Ibn `Abbas:
حَدَّثَنَا عَلِيٌّ ، حَدَّثَنَا سُفْيَانُ ، حَدَّثَنَا يَحْيَى بْنُ سَعِيدٍ ، قَالَ سَمِعْتُ عُبَيْدَ بْنَ حُنَيْنٍ ، قَالَ سَمِعْتُ ابْنَ عَبَّاسٍ ـ رضى الله عنهما ـ يَقُولُ أَرَدْتُ أَنْ أَسْأَلَ عُمَرَ فَقُلْتُ يَا أَمِيرَ الْمُؤْمِنِينَ مَنِ الْمَرْأَتَانِ اللَّتَانِ تَظَاهَرَتَا عَلَى رَسُولِ اللَّهِ صلى الله عليه وسلم فَمَا أَتْمَمْتُ كَلاَمِي حَتَّى قَالَ عَائِشَةُ وَحَفْصَةُ.
I intended to ask `Umar so I said, "Who were those two ladies who tried to back each other against the Prophet?" I hardly finished my speech when he said, They were `Aisha and Hafsa."