"The Prophet (Allah bless him and give him peace) used to fast until we would say: “He does not intend to break fast ,” and he used to break fast until we would say: “He does not intend to fast during it.” He did not fast for a whole month after arriving in Medina, with the exception of Ramadan.”
"I did not see Allah’s Messenger (Allah bless him and give him peace) fast in any month more than his fasting for Allah’s sake in Sha'ban. He used to keep fast through all but a little of Sha'ban; no indeed, he used to keep fast through all of it!”
Narrated Humaid ibn Anas ibn Malik reported that he was asked about the fasting of the Prophet (Allah bless him and give him peace), so he said:
"He used to fast during the month until we would assume that he did not intend to break fast during it, and he used to break fast until we would assume that he did not intend to fast during any of it. You would not wish to assume that he was performing the ritual prayer during the night, unless you saw him performing the ritual prayer, nor that he was sleeping, unless you saw him sleeping.”
