سنن النسائي

It was narrated that 'Abdullah bin Shaqiq said: "I asked 'Aishah about the fasting of the Messenger of Allah. She said: "The Messenger of Allah (ﷺ) used to fast until we said: He is going to (continue to) fast, and he used not to fast until we said: He is not going to, and he did not fast for a whole month from the time he came to Al-Madinah, apart from Ramadan."'