(70) باب صَوْمِ النَّبِيِّ صلى الله عليه وسلم - بِأَبِي هُوَ وَأُمِّي - وَذِكْرِ اخْتِلاَفِ النَّاقِلِينَ لِلْخَبَرِ فِي ذَلِكَ
It was narrated from Usamah bin Zaid:
That the Messenger of Allah used to fast continually and it ws said that he would not break his fast, and he used not to fast and it was said that he would not fast.
Reference: Sunan an-Nasa'i 2359
In-book reference: Book 22, Hadith 270
English translation: Vol. 3, Book 22, Hadith 2361