The Book of Fasting (Kitab Al-Sawm)

Muslim :: Book 6 : Hadith 2423

Ibn Abi Aufa (Allah be pleased with him) reported: We were with the Messenger of Allah (may peace be upon him) on a journey. When the sun sank he said to a person: Get down and prepare barley meal for us. Upon this he said: Messenger of Allah, let there be dusk. (He the Holy Prophet) said: Get down and prepare barley meal for us. He (the person) said: There is still (the light of) day upon us. (But) he got down (in obedience to the command of the Holy Prophet) and prepared a barley meal for him and he (the Holy Prophet) drank that (liquid meal) and then said: When you see the night approaching from that side (west) (and he pointed towards the east with his hand), then the observer of the fast should break it.

Source materials are from the University of Southern California MSA site
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