It was narrated to me by Humayd ibn Mas'adah al-Bahili, who said: Bishr ibn al-Mufaddal narrated to us, who said: Salamah — and he is Ibn 'Alqamah — narrated to us, from Nafi', from 'Abdullah ibn 'Umar, may Allah be pleased with them both, who said: The Messenger of Allah, peace and blessings be upon him, said: "The month is twenty-nine days. So when you see the crescent, fast, and when you see it, break your fast. But if it is obscured from you, then complete its count."