Sunan Ibn Majah, Volume 2, Book 7, Hadith 1711 (DarusSalam) ⓘ

It was narrated that Ibn ‘Abbas said: “The Messenger of Allah used to fast until we thought he would never stop fasting. And he used to not fast until we thought we would never fast. And he never fasted any compelte month apart from Ramadan, from the time he came to Al- Madinah.”

حَدَّثَنَا مُحَمَّدُ بْنُ بَشَّارٍ، حَدَّثَنَا مُحَمَّدُ بْنُ جَعْفَرٍ، حَدَّثَنَا شُعْبَةُ، عَنْ أَبِي بِشْرٍ، عَنْ سَعِيدِ بْنِ جُبَيْرٍ، عَنِ ابْنِ عَبَّاسٍ، قَالَ كَانَ رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ يَصُومُ حَتَّى نَقُولَ لاَ يُفْطِرُ وَيُفْطِرُ حَتَّى نَقُولَ لاَ يَصُومُ ‏.‏ وَمَا صَامَ شَهْرًا مُتَتَابِعًا إِلاَّ رَمَضَانَ مُنْذُ قَدِمَ الْمَدِينَةَ ‏.‏