Sayyiduna Sahl bin Sa’d (may Allah be pleased with him) narrated that the verse was revealed:“Eat and drink until the white thread becomes distinct to you from the black thread”(Al-Baqarah 187), but the words“of the dawn”had not yet been revealed. Because of this, some people, when intending to fast, would take a black and a white thread and tie them to their feet, and they would not stop eating and drinking until both threads became clearly visible. Then Allah the Exalted revealed the words“of the dawn,”and then people realized that what was meant was the night and the day.