#21 Crescent
Book of Praying at Night in Ramadaan (Taraweeh)
(1) Chapter: The superiority of Nawafil at night in Ramadan
Sahih al-Bukhari 2008
Narrated Ibn `Umar:
I heard Allah’s Messenger (صلى الله عليه و سلم) saying, “When you see the crescent (of the month of Ramadan), start fasting, and when you see the crescent (of the month of Shawwal), stop fasting; and if the sky is overcast (and you can’t see it) then regard the month of Ramadan as of 30 days.”