Narrated `Abdullah bin `Umar:
Allah's Messenger (ﷺ) said, "The month (can be) 29 nights (i.e. days), and do not fast till you see the moon, and if the sky is overcast, then complete Sha'ban as thirty days."
Reference | : Sahih al-Bukhari 1907 |
In-book reference | : Book 30, Hadith 17 |
USC-MSA web (English) reference | : Vol. 3, Book 31, Hadith 131 |
(deprecated numbering scheme) |