Uthman bin Hakeem reported,

I asked Saeed bin Jubayr about fasting in Rajab, and he said, "Ibn Abbas informed me that the Messenger of Allah ﷺ used to fast so much that we would say he never broke his fast, and he would refrain from fasting so much that we would say he never fasted."

حدثنا إبراهيم بن موسى حدثنا عيسى

حدثنا عثمان يعني ابن حكيم قال

سألت سعيد بن جبير عن صيام رجب فقال أخبرني ابن عباس أن رسول الله ﷺ كان يصوم حتى نقول لا يفطر ويفطر حتى نقول لا يصوم