"I said: 'O Messenger of Allah, sometimes you fast, and you hardly ever break your hardly ever fast, except two days which, if you are fasting, you include them in your fast, and if you are not fasting, then you fast them on your own.' He said: 'Which two days?' I said: 'Monday and Thursday.' He said: 'Those are two days in which deeds are shown to the Lord of the worlds, and I like my deeds to be shown (to Him) when I am fasting."'  

قُلْتُ يَا رَسُولَ اللَّهِ إِنَّكَ تَصُومُ حَتَّى لاَ تَكَادَ تُفْطِرُ وَتُفْطِرُ حَتَّى لاَ تَكَادَ أَنْ تَصُومَ إِلاَّ يَوْمَيْنِ إِنْ دَخَلاَ فِي صِيَامِكَ وَإِلاَّ صُمْتَهُمَا قَالَ أَىُّ يَوْمَيْنِ قُلْتُ يَوْمَ الاِثْنَيْنِ وَيَوْمَ الْخَمِيسِ قَالَ ذَانِكَ يَوْمَانِ تُعْرَضُ فِيهِمَا الأَعْمَالُ عَلَى رَبِّ الْعَالَمِينَ فَأُحِبُّ أَنْ يُعْرَضَ عَمَلِي وَأَنَا صَائِمٌ  

The Messenger of Allah ﷺ used to alternate between fasting and not fasting: Sometimes it would be said, "Do not break your fast," and other times it would be said, "Do not fast."

I asked, "O Messenger of Allah, you fast so much that it seems you would almost never break from fasting, and you do not fast so often that it seems you would almost never fast ˹again˺ except for two days if they were to enter during your fasting except your would fast in them." He asked, "Which two days?" I said, "Mondays and Thursdays." He replied, "These are days when deeds are presented to the Lord of the worlds, so I love for my deeds to be presented while I am fasting."  

كَانَ رَسُولُ الله ﷺ يَسْرُدُ الصَّوْمَ فَيُقَالُ: لَا يُفْطِرُ، وَيُفْطِرُ فَيُقَالُ: لَا يَصُومُ۔

قُلتُ: يَا رَسُولَ الله: إِنَّكَ تَصُومُ حَتَّى لَا تَكَادَ تُفْطِرُ، وَتُفْطِرُ حَتَّى لَا تَكَادَ أَنْ تَصُومَ إِلَّا يَوْمَيْنِ إِنْ دَخَلَا فِى صِيَامِكَ وَإلَّا صُمْتَهُمَا، قَالَ: «أَىُّ يَوْمَيْنِ؟» قُلتُ: يَوْمُ الاثْنَيْنِ، وَيَوْمُ الْخَميس، قَالَ: «ذانِكَ يَوْمَانِ تُعْرَضُ فِيهمَا الأَعمَالُ عَلَى رَبِّ الْعَالمِينَ، فَأُحِبُّ أَنْ يُعْرَضَ عَمَلِى وَأَنَا صَائِمٌ۔»