Salim narrates from his father (Sayyiduna Abdullah bin Umar, may Allah be pleased with them both): Once he saw the crescent of Shawwal during the day, so Sayyiduna Abdullah bin Umar, may Allah be pleased with them both, said: "It is not lawful for you to break your fast until you see the crescent of the first (of Shawwal) at the time when it is usually seen (i.e., at night)."