سَمِعْتُ أَبَا عَبْدِ اللَّهِ ع يَقُولُ كَانَ رَسُولُ اللَّهِ ص يَصُومُ حَتَّى يُقَالَ لَا يُفْطِرُ وَ يُفْطِرُ حَتَّى يُقَالَ لَا يَصُومُ ثُمَّ صَامَ يَوْماً وَ أَفْطَرَ يَوْماً ثُمَّ صَامَ الْإِثْنَيْنِ وَ الْخَمِيسَ ثُمَّ آلَ مِنْ ذَلِكَ إِلَى صِيَامِ ثَلَاثَةِ أَيَّامٍ فِي الشَّهْرِ- الْخَمِيسِ فِي أَوَّلِ الشَّهْرِ وَ أَرْبِعَاءَ فِي وَسَطِ الشَّهْرِ وَ خَمِيسٍ فِي آخِرِ الشَّهْرِ وَ كَانَ ص يَقُولُ ذَلِكَ صَوْ
"I heard Abu Abdullah (Imam Jafar ibn Muhammad Al-Sadiq (as)) say: 'The Messenger of Allah (swt) (peace and blessings be upon him and his family) would fast so much that it was said he would never break his fast, and he would break his fast so much that it was said he would never fast. Then he began fasting one day and