عَنْ عَائِشَةَ رَضِيَ اللَّهُ عَنْهَا قَالَتْ: كَانَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَعَلَى آلِهِ وَصَحْبِهِ وَسَلَّمَ يَصُومُ حَتَّى نَقُولَ لَا يَفْطِرُ، وَيُفْطِرُ حَتَّى نَقُولَ لَا يَصُومُ، وَمَا اسْتَكْمَلَ شَهْرًا قَطُّ إِلَّا رَمَضَانَ، وَمَا رَأَيْتُهُ فِي شَهْرٍ قَطُّ أَكْثَرَ صِيَامًا مِنْهُ فِي شَعْبَانَ
Narrated by Sayyida Aisha (may Allah be pleased with her), she says: Sometimes the Messenger of Allah (peace and blessings be upon him) would fast so frequently that we would say he will not stop fasting, but then he would leave fasting for such a long period that we would think he will not observe voluntary fasts anymore. The Messenger of Allah (peace and blessings be upon him) did not fast an entire month except for Ramadan, and I did not see him fast in any month more than he did in Sha’ban.