Sayyiduna ‘Adi bin Hatim (may Allah be pleased with him) says: When the verse:“Until the white thread becomes distinct to you from the black thread...”(Surah Al-Baqarah: 187) was revealed, I took a black rope and a white rope and placed them under my pillow, and during the night I kept looking at them, but I could not discern anything. In the morning, I went to the Messenger of Allah (peace and blessings be upon him) and mentioned this to him. He said:“That (black thread) is the darkness of the night, and (white thread) is the whiteness of the morning.”