"The Messenger of Allah said: "The Messenger of Allah said: Do not fast before Ramadan. Fast when you see it and stop fasting when you see it, and if clouds prevent you from seeing it, then complete Thirty (Days)."'
Sunan an-Nasa'i Book 22, Hadith 41
← Previous Hadith "Fast when you see it, and stop fasting when you see it, and if clouds prevent you from seeing it, then complete the number, and do not fast ahead of Ramadan."

Sunan an-Nasa'i Book 22, Hadith 40 Next Hadith → "The Messenger of Allah swore not to come to his wives for a month, and twenty-nine days passed. I said: 'Did you not wives to keep away from you wives for a month? I have counted twenty-nine days.' The Messenger of Allah said: 'The month is twenty-nine days."'

Sunan an-Nasa'i Book 22, Hadith 42