"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
← Previous Hadith "The Messenger of Allah said: 'When you see the crescent then fast, and when you see it, then stop fasting. If it is too cloudy then complete Shaban as thirty days, unless you see the crescent before that, then fast Ramadan as thirty days, unless you see the new crescent before that."'

Sunan an-Nasa'i Book 22, Hadith 39 Next Hadith → "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