Khalid bin al-Harith bin 'Ubaid خالد بن الحارث بن عبيد · The Book of Fasting

"I asked Aishah: 'Tell me about the fasting of the Messenger of Allah.' She said: 'he used to fast until we said: he is going to fast until we said: He is not going to fast. He never fasted any month more than Shaban. He used to fast (all) of Shaban except a little, he used to fast all of Shaban."' '

the Messenger of Allah saw some people gathered around a man, so he asked (what was happening) and they said: "It is a man who is exhausted because of fasting." The Messenger of Allah said: "It is not righteousness to fast when traveling."