وَعَنِ ابْنِ عَبَّاسٍ
قَالَ: كَانَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: لَا يُفْطِرُ أَيَّامَ الْبيض فِي حضر وَلَا فِي سفر
It was the custom of God’s messenger not to eat on the middle days* of the month whether travelling or not. *Literally, the days of the white (nights). These are the days following the thirteenth, fourteenth, and fifteenth nights of the month, the nights when there is most moonlight. Nasai transmitted it.
Mishkat al-Masabih 1980, Book 8, Fasting, Hadith 114. 1 min read