The Book of Fasting (Kitab Al-Sawm)

Muslim :: Book 6 : Hadith 2396

'Adi b. Hatim (Allah be pleased with him) reported that when (this verse) was revealed:" Until the white streak of the dawn becomes distinct from the dark streak" (ii. 187) Adi b. Hatim said: Messenger of Allah, verily I keep underneath my pillow two strings, one white and the other black, by which I distinguish night from dawn. Upon this the Messenger of Allah (may peace be upon him) said: Your pillow seems to be very large. For the word khait implies the blackness of the night and the whiteness of the dawn.

Source materials are from the University of Southern California MSA site
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