Sunan an-Nasa'i 2186
سنن النسائي#2186Sahihأَخْبَرَنِي عَمْرُو بْنُ عُثْمَانَ، عَنْ بَقِيَّةَ، قَالَ حَدَّثَنَا بَحِيرٌ، عَنْ خَالِدٍ، عَنْ جُبَيْرِ بْنِ نُفَيْرٍ، أَنَّ رَجُلاً، سَأَلَ عَائِشَةَ عَنِ الصِّيَامِ، فَقَالَتْ إِنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم كَانَ يَصُومُ شَعْبَانَ كُلَّهُ وَيَتَحَرَّى صِيَامَ الاِثْنَيْنِ وَالْخَمِيسِ .
It was narrated from Jubair bin Nufair that a man asked Aishah about fasting and she said:"The Messenger of Allah used to fast all of Shaban, and he made sure to fast on Mondays and Thursdays
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Abu GhuddahSahih
Al-AlbaniSahih
Zubair Ali ZaiSahih
In-book reference: 22:97