Sayyiduna Bara’ bin Azib (may Allah be pleased with them both) said: In the early days of Islam, when the companions of the Messenger of Allah (peace and blessings be upon him) were fasting and the time for breaking the fast came, if any fasting person slept before breaking his fast, then he could not eat that night nor the following day until evening. Then it happened that Sayyiduna Qais bin Sirmah Al-Ansari (may Allah be pleased with him) was fasting. When the time for breaking the fast came, he went to his wife and said:“Do you have anything to eat?”She said:“At this moment, there is nothing, but I will go and bring something.”Qais had worked all day, so he fell asleep. When his wife returned, she saw him sleeping and said:“Alas, you have been deprived.”When it was midday, Qais fainted. When this was mentioned to the Prophet (peace and blessings be upon him), this verse was revealed: «أُحِلَّ لَكُمْ لَيْلَةَ الصِّيَامِ الرَّفَثُ إِلَى نِسَائِكُمْ ......» [بقره: 187/2] meaning:“It has been made lawful for you to go to your wives on the nights of fasting.”Upon this, the companions (may Allah be pleased with them) were very happy and they ate and drank until the white thread (of dawn) became distinct to them from the black thread.

Sayyiduna ‘Adi bin Hatim (may Allah be pleased with him) said: When this verse: «وَكُلُوا وَاشْرَبُوا حَتَّى يَتَبَيَّنَ لَكُمُ الْخَيْطُ الْأَبْيَضُ مِنَ الْخَيْطِ الْأَسْوَدِ مِنَ الْفَجْرِ» [بقرة: 187/2] was revealed, I said: O Messenger of Allah! I placed a white thread and a black thread under my pillow, but nothing became clear to me. The Messenger of Allah (peace and blessings be upon him) said:“You have a big pillow! What is meant is the darkness of the night and the whiteness of the day.”